The American Ceramic Society 2018 Conference on Electronic ...ceramics.org/.../2018/01/EAM18_Abstracts_WebFinal.pdf · 2 Electronic and Advanced Materials 2018 Introduction This volume

The American Ceramic Society

2018 Conference on Electronic andAdvanced Materials (EAM 2018)

ABSTRACT BOOK

January 17–19, 2018Orlando, Florida

2 Electronic and Advanced Materials 2018

IntroductionThis volume contains abstracts for over 300 presentations during the 2018 Conference on Electronic and Advanced Materials (EAM 2018) in Orlando, Florida. The abstracts are reproduced as submitted by authors, a format that provides for longer, more detailed descriptions of papers. The American Ceramic Society accepts no responsibility for the content or quality of the abstract content. Abstracts are arranged by day, then by symposium and session title. An Author Index appears at the back of this book. The Meeting Guide contains locations of sessions with times, titles and authors of papers, but not presentation abstracts.

How to Use the Abstract BookRefer to the Table of Contents to determine page numbers on which specific session abstracts begin. At the beginning of each session are headings that list session title, location and session chair. Starting times for presentations and paper numbers precede each paper title. The Author Index lists each author and the page number on which their abstract can be found.

Copyright © 2018 The American Ceramic Society (www.ceramics.org). All rights reserved.

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Copyright © 2018. The American Ceramic Society (www.ceramics.org). All rights reserved.

Electronic and Advanced Materials 2018 3

Table of ContentsPlenary Session I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

BASIC SCIENCE DIV S3: Experimental and Theoretical Insights on Interfaces of Ceramics

Experimental and theoretical insights on interfaces of ceramics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

BASIC SCIENCE DIV S5: Morphology Evolution and Microstructure Characterization

Experimental Studies of Microstructure Evolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

ELECTRONICS DIV S2: Energy Applications of Electronic and Ferroic Ceramics: Synthesis, Characterization, and Theory

Energy Applications of Electronic and Ferroic Ceramics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

ELECTRONICS DIV S6: Electronics Materials for 5G Telecommunications Applications

Electronics Materials for 5G Telecommunications Applications I . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

ELECTRONICS DIV S10: Synthesis and Processing Science of Thin Films and Single Crystals - The Details of Engineering Structure-Property Relationships

Pioneers in Synthesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

ELECTRONICS DIV S11: Superconducting Materials and Applications

Superconducting Materials I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

ELECTRONICS DIV S12: Thermal Transport and Storage in Functional Materials and Devices

Thermal Transport and Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

ELECTRONICS DIV S13: Advanced Electronic Materials: Processing, Structure, Properties, and Applications

Advanced Electronic Materials I: Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

BASIC SCIENCE DIV S4: Fundamentals of Mechanical Response

Mechanical Behavior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20



Modeling and Characterization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21


Electronics Materials for 5G Telecommunications Applications II . . . . . . . . . . . . . . . . . . . . . . . . . . 23

ELECTRONICS DIV S8: Multifunctional Nanocomposites

Thin Film Growth: A STEM Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Thin Film Growth and Functionalities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

ELECTRONICS DIV S9: Substitution and Sustainability in Functional Materials and Devices

Substitition and Sustainability in Functional Materials I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26


Refined Synthesis Routes to Advance and Enable Properties I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Refined Synthesis Routes to Advance and Enable Properties II . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29


Superconducting Materials II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30


Advanced Electronic Materials II: Ferroelectric Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Reliability of Electronic Materials and Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Poster Session . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34

Plenary Session II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41


Processing to Control Microstructure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Joint Session: Basic Science Symp 1 and Electronics Symp 4

Defect Physics and Chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42


ELECTRONICS DIV S1: Complex Oxide and Chalcogenide Semiconductors: Research and Applications

Emerging Chalcogenide Materials for Electronic, Photonic and Energy Applications . . . . . . . 44

ELECTRONICS DIV S3: Multiscale Structure-property Relationships and Advanced Characterization of Functional Ceramics

Imaging and Analytical Techniques I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

ELECTRONICS DIV S7: Mesoscale Phenomena in Ceramic Materials

Mesoscale Phenomena in Ceramic Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46


Coupling between Ferroelectricity and Ferromagnetism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47


Substitition and Sustainability in Functional Materials II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48


Lead Free Piezoelectric and Dielectrics for Energy Storage and Conversion . . . . . . . . . . . . . . . . 50

BASIC SCIENCE DIV S1: Computational and Data Sciences for 21st Century Ceramics Research

Ferroelectrics and Other Functional Ceramics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

Material Interfaces: Structure, Properties and Evolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

BASIC SCIENCE DIV S2: Electromagnetic Field Effects on Ceramic Processing: Fundamental Mechanisms and New Applications

Electromagnetic Field Effects on Ceramic Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53


Complex Oxide Heterostructures: Effect of Dimensionality and Correlation . . . . . . . . . . . . . . . . 55


Multiscale Structure-property Relationships I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56


ELECTRONICS DIV S4: Agile Design of Electronic Materials: Aligned Computational and Experimental Approaches

Materials by Design: Computational/experimental Emerging Strategies for Searching, Designing, and Discovering New Electronic Materials . . . . . . . . . . . . . . . . . . . . . . . . . . 58

ELECTRONICS DIV S5: Ion-conducting Ceramics

Cation Conducting Ceramics for Energy Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Mechanisms for Ion Transport . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61


Strain Effect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Ferroelectricity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63


Characterization of Materials I: Crystal Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

Advanced Electronic Materials III: Piezoelectric Crystals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65


Data Science and High-throughput Approaches I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66


Chalcogenide Thin Films and Heterostructures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68


Imaging and Analytical Techniques II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

Multiscale Structure Property Relationships II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71


Novel Ion Conducting Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

Oxygen Conductors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73


Transport . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

Magnetism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75



Materials Design, New Materials and Structures, Their Emerging Applications (I) . . . . . . . . . . . 76

Characterization of Materials II: Crystal Structure and Properties . . . . . . . . . . . . . . . . . . . . . . . . . . 77


Data Science and High-throughput Approaches II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79


Growth and Characterization of Oxides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80


Functionalities: Electronic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

Functionalities: Electrochemical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81


Materials Design, New Materials and Structures, Their Emerging Applications II . . . . . . . . . . . 82

*Denotes Presenter Electronic and Advanced Materials 2018 9

Abstracts

Wednesday, January 17, 2018

Plenary Session IRoom: Orange DSession Chair: Wayne Kaplan, Technion - Israel Inst of Tech

8:40 AM(EAM-PLEN- 001-2018) Using transport studies to reveal the myriad secrets of SrTiO3

R. A. De Souza*1

1. RWTH Aachen University, Institute of Physical Chemistry, Germany

There is renewed interest in electrical conduction in the perovskite oxide SrTiO3, driven by the material’s possible application in devices for all-oxide electronics and resistive switching. In my talk, I will briefly review, first, the defect chemistry of SrTiO3, and then, the thermodynamics of space-charge formation at extended defects. The main part of the talk will concentrate on understanding the electrical conductivity of single crystal, bicrystal and thin film samples of this prototypical perovskite-type oxide. In particular I will focus on the conductivity behavior of the bulk phase as a function of temperature (from room temperature up to ca. 700 °C), of bicrystal samples as a function of misorientation angle, and of thin-film samples as a func-tion of film thickness. For all three cases I will demonstrate that it is possible to predict the electrical conductivity using thermodynamic models. Finally, I will describe the consequences for memresis-tive devices, and I will draw attention to current challenges and outstanding problems.

BASIC SCIENCE DIV S3: Experimental and Theoretical Insights on Interfaces of Ceramics

Experimental and theoretical insights on interfaces of ceramicsRoom: Nautilus CSession Chair: Christina Scheu, Max-Planck-Institute for Eisenforschung GmbH

10:00 AM(EAM-BASIC-S3-001-2018) Dynamic simulation of oxygen transport through oxide films (Invited)M. P. Tautschnig1; N. M. Harrison1; M. W. Finnis*1

1. Imperial College London, United Kingdom

We introduce a microscopic model for describing time-dependent ionic transport along grain boundaries through thin oxide films, in which the mobile species are vacancies, electrons and holes. The grain structure is idealized as a lattice of identical columnar grains with hexagonal cross-section. Reactions with the environment constitute the boundary conditions that drive the transport between the surfaces. Simulations have been carried out to solve the Poisson equation self-consistently with the Nernst-Planck flux equations for the mobile species. The model has been applied to published exper-imental data on oxygen permeation through alumina in the form of a membrane and reproduces the hypothesized transition between p-type and n-type ionic conductivity of the alumina grain bound-aries as a function of the applied oxygen gas pressure. The equations and results are compared and contrasted with those of the 1 dimen-sional Wagner model. The three-dimensional model we develop here is readily adaptable to problems such as transport in a solid state electrode, or corrosion scale growth.

10:30 AM(EAM-BASIC-S3-002-2018) Understanding grain structure and phase coexistence in ferroelectric HfO2 by STEM and crystal chemistryE. D. Grimley*1; T. Schenk2; T. Mikolajick2; U. Schroeder2; J. LeBeau1

1. North Carolina State University, Materials Science and Engineering, USA2. NaMLab gGmbH, Germany

Through the efforts of many studies, the ferroelectric behavior of polycrystalline thin-film hafnia (HfO2) has been broadly correlated to the many polymorphs present in the films. Most as-processed films possess multiple phases, and additional evidence suggests that phase fractions evolve with field-cycling. In spite of the importance of the coexistence of multiple phases in these films, little is known of the nanoscale grain structure and its ability to facilitate phase trans-formation. In this presentation, we provide a comprehensive study of the mechanisms of phase coexistence using scanning transmis-sion electron microscopy which we present in the context of crystal chemistry. Our results reveal that while some grains are mono-do-main and exist without clear orientation relationship to neighboring grains, others possess planar defects and/or multiple phases with coherent internal boundaries. We discuss the preferential formation of certain sets of monoclinic/orthorhombic interphase boundaries. These orientations are considered in terms of lattice compatibility, and we will present how misfit influences boundary steps and the transition in symmetry between the adjacent phases. These findings have important consequences for both epitaxial strain within the grain and for the possibility of phase transformation by interphase boundary motion, both of which will be discussed.

10:45 AM(EAM-BASIC-S3-003-2018) δ-Doping Effects on Electronic and Energetic Properties of LaAlO3/SrTiO3 Heterostructure: First-Principles Analysis of 23 Transition-Metal DopantsJ. Cheng1; J. Luo1; K. Yang*1

1. University of California San Diego, Department of NanoEngineering, USA

The two-dimensional electron gas (2DEG) formed at the inter-face between two insulating perovskite oxides such as LaAlO3 and SrTiO3 provides a playground for developing all-oxide elec-tronic devices, though improving the 2DEG mobility is still a great challenge. One possible way of improving the 2DEG mobility is via δ-doping at the heterointerface. Here we studied the electronic and energetic properties of δ-doped LaAlO3/SrTiO3 with 23 transi-tion-metal dopants from group 3 to group 10 using first-principles calculations. We found a clear trend for the electron effective mass and interfacial energy change in the δ-doped LaAlO3/SrTiO3 with various dopants, and there exists a trade-off between achieving light effective mass bands and forming energetically favorable struc-tures. We found that the Fe, Co, Ni, Ru, Rh, Pd, Os and Ir could also serve as promising candidate dopants to produce light effective mass bands and relatively large energetic stability, in addition to the experimentally confirmed Mn dopant. Our findings provide a wide avenue to increase the 2DEG mobility in the LaAlO3/SrTiO3 hetero-structure via δ-doping with transition metals.

11:00 AM(EAM-BASIC-S3-004-2018) STEM Imaging and Analysis of Defects and Interfaces in Complex Oxides (Invited)D. W. McComb*1

1. The Ohio State University, USA

The spatial resolution achievable in an aberration-corrected scan-ning transmission electron microscopy (STEM) yields the tantalizing prospect of being able to analyze chemistry at defects and inter-faces on the atomic scale using the elastic and inelastic scattering signals. I will review recent investigations in the perovskite type La0.67Sr0.33MnO3/LaAlO3 system where atomic resolution imaging

10 Electronic and Advanced Materials 2018 *Denotes Presenter

Abstracts

and spectroscopic techniques are combined to determine the complex atomic and chemical structure of misfit dislocations. I will also discuss investigation of half-metallic double perovskites of the general formula A2BB'O6 that are of great interest for their possible application in spintronic devices, because they exhibit ferrimagne-tism with high Curie temperatures (TC) and a high degree of spin polarization. Using aberration-corrected high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM), we investigate ordering phenomena in epitaxial thin films of the double perovskite Sr2CrReO6. Experimental and simulated imaging and diffraction are used to identify antiphase domains in the films. Image simulation provides insight into the effects of atomic-scale ordering along the beam direction on HAADF-STEM intensity. I will review the challenges and limitations of the methods, with specific reference to investigation of defects and interfaces, and will discuss prospects for the future.

11:30 AM(EAM-BASIC-S3-005-2018) Effect of a single grain boundary on resistance degradation of bicrystal SrTiO3

J. Carter*1; T. J. Bayer1; C. Randall1

1. Pennsylvania State University, Materials Science and Engineering, USA

Grain boundaries in dielectric materials are known to prevent resis-tance degradation at elevated temperatures and voltages. However, all polycrystalline dielectrics have a large variety of grain bound-aries at various orientations and sizes, which causes great difficulty when drawing structure-property relationships. Strontium titanate bicrystals, having a single boundary with defined tilt angle are well suited for exploring the electrical properties of a grain boundary, as the electrical properties of strontium titanate single crystals have been studied at length. In this study, modulus spectroscopy (an impedance formalism) and thermally stimulated depolarization current (TSDC) techniques are used to elucidate the interaction of the oxygen vacancy with the grain boundary at various tempera-tures, electric fields, and grain boundary orientations with respect to the applied field. The TSDC signal related to oxygen vacancies is completely suppressed when the grain boundary is normal to the electric field.

11:45 AM(EAM-BASIC-S3-006-2018) Bicrystal piezotronicsJ. Rödel*1; P. Keil1; T. Frömling1; M. Trapp1; H. Kleebe1; N. Novak1

1. Technische Universität Darmstadt, Germany

The term piezotronics refers to electronic devices, whose electrical conductivity can be tuned by altering electrostatic potential barriers by mechanical stress through the piezoelectric effect. This presenta-tion describes the approach of inserting the chemistry (defining the distribution of interfacial defect states) of a polycrystalline varistor ceramic into a bicrystal interface with well-defined polarization conditions. We will show how stress can tune the potential barrier in head-to-head and tail-to-tail orientation of the polarization vector to enhance/lower the conductivity across ZnO bicrystal interfaces. The methodology is based on bonding two well-aligned single crys-tals of ZnO with an intermediate thin polycrystalline sacrificial layer of doped ZnO. Subsequent high temperature treatment grows the single crystals into the sacrificial layer and consumes the poly-crystalline materials either partially or fully. The applied process can provide structures with a maximized figure of merit for stress sensing applications as well as model structures to study the physical interaction between stress-induced piezoelectric polarization and the electrostatic potential at ZnO bicrystal interfaces. The discussion on the piezotronic effect will be complemented by a study of the interfa-cial structure via high-resolution transmission electron microscopy.

12:00 PM(EAM-BASIC-S3-007-2018) Thermal conductivity measurements of ceramic composites with the 3 omega methodA. W. Travis*1; M. Mecartney1

1. University of California, Irvine, USA

The 3 omega method is used for determining the thermal conduc-tivity of various ceramic composites of varying grain sizes to understand the role of heterointerfaces on the interfacial thermal resistance (or Kapitza resistance). The system under investigation is equal volume alumina, magnesium aluminum spinel, and 8-mol% yttria-stabilized zirconia with grain sizes ranging from 150 nm to 1.2 microns. The Kapitza resistance is determined from the experi-mental values as well as the intrinsic, grain size independent thermal conductivity calculated from finite element analysis simulations on real microstructures. Preliminary studies show that the onset of Kapitza resistance in composites with heterointerfaces may become a factor at larger grain sizes than in single phase materials with only grain boundaries between like phases. 3 omega thermal conductivity results are also compared to data obtained from the combination of laser flash analysis, differential scanning calorimetry, and dilatom-etry for both single phase and composite systems. The differences in thermal conductivity values from heterointerfaces and grain boundaries will be discussed. Engineering microstructures with heterointerfaces with high Kapitza resistance may lead to materials with very low thermal conductivity.


Experimental Studies of Microstructure EvolutionRoom: Nautilus BSession Chair: Helen Chan, Lehigh University

10:00 AM(EAM-BASIC-S5-001-2018) Grain Boundary Migration in Polycrystals: A disconnection perspective (Invited)D. J. Srolovitz*1; J. Han1; S. Thomas1; K. Chen1; Y. Xiang2; L. Zhang2

1. University of Pennsylvania, Materials Science & Engineering, USA2. Hong Kong University of Science and Technology, Mathematics,

Hong Kong

This talk addresses how grain boundaries (GBs) migrate via the motion of disconnections along the GB within a polycrystal. First, we review the relationship between disconnections and the under-lying bicrystallography; this relationship determines the set of all allowed Burgers vector and step heights for each GB {b,h}. Next, we show how GBs move under no driving force and for different driving forces. In particular, we discuss GB roughening, intrinsic mobility, and why GB mobility depends on the nature of the driving force. We apply this picture to understand the motion GBs in a bicrystal and derive a continuum equation of motion for GBs. We then turn to the role of triple juctions TJs and show that it is remarkable that TJ move at all. We examine what it takes to move a GB and how the flexibility of GB dynamics make this possible. Finally, we conclude with some general remarks on GB migration in polycrystals.

10:25 AM(EAM-BASIC-S5-002-2018) 3D observations of the evolution of grain morphology during grain growth (Invited)A. Bhattacharya1; Y. Shen1; C. Hefferan1; S. Li1; J. lind1; R. Suter1; G. Rohrer*1

1. Carnegie Mellon University, USA

The three-dimensional structure of polycrystalline Ni was measured at five points in time separated by 30 min anneals at 800 °C. The locations, orientations, and shapes of roughly 2000 grains were


Abstracts

determined at each time step by near field high-energy diffrac-tion microscopy. The data make it possible to determine the grain boundary (GB) character distribution, the relative GB energies, and the GB curvature distribution at each time during the interrupted thermal annealing. Using size, orientation, and location as selection criteria, individual grains were identified and tracked throughout multiple anneal states. These data make it possible to compare the changes in volume with time to a grain’s volume, numbers of faces, integral mean curvature, and the characteristics of its neighbors. The findings for individual grains and ensemble averages are compared with established theories for grain growth. We found that for individual grains, morphological evolution is strongly influenced by the grain’s neighbors.

10:50 AM(EAM-BASIC-S5-003-2018) Morphological Changes in Oxides Doped with Nickel: The Role of Oxide Particle Size (Invited)I. Reimanis*1; A. Morrissey2

1. Colorado School of Mines, USA2. CoorsTek, USA

Transition metal oxide dopants such as nickel oxide are known to influence the sintering, microstructure development, and prop-erties of ceramics. Nickel oxide in particular is interesting and technologically very useful especially for catalysts and fuel cells which experience reduction/oxidation (redox) conditions. This presentation will describe the very different roles of nickel in redox conditions in two different ceramic systems, yttria stabilized zirconia (YSZ) and barium yttrium zirconate (BZY). The magnetic state of nickel is tracked with SQUID magnetometry to help establish its role during processing in air and during exposure to reducing conditions under which metallic nickel is formed. When the particle size of YSZ or BZY is at the nanoscale, nickel ions or nickel oxides develop monolayer coverage, but as the particles coarsen, new nickel oxide phases appear. The behavior under subsequent redox conditions depends strongly on this starting microstructure arrangement.

11:15 AM(EAM-BASIC-S5-004-2018) Impact of Fe-dopant on grain growth in strontium titanate: Experimental evidence for solute dragW. Rheinheimer*1; M. J. Hoffmann2

1. Karlsruhe Institute of Technology, Institute for Applied Materials, Germany

2. University of Karlsruhe, Institute for Applied Materials (IAM-KM), Germany

The present study investigates the impact of acceptor dopants on grain growth in strontium titanate. While undoped microstructures show normal grain growth at low temperatures (<1350°C), doped microstructures evolve bimodally: with increasing acceptor dopant concentration an increasing population of small grains arises. At a concentration of 5 mol% Fe, hardly any grain growth is evident and the grain size stays close to the powder particle size (~300nm). It was shown before via TEM and EDS that Fe segregates to the interfaces due to its negative charge and a positive boundary poten-tial. Thus the experimental findings seem to be well explained by the theory of solute drag: the diffusion of segregated defects (‘solutes’) at interfaces can retard grain boundary migration. This retardation depends on the defect concentration and on the local driving force. Possible implications for the grain growth transition of strontium titanate are discussed.

11:30 AM(EAM-BASIC-S5-005-2018) Influence of Defect Chemistry on the Grain Growth of Barium Strontium TitanateF. J. Altermann*1; W. Rheinheimer1; M. J. Hoffmann1

1. Karlsruhe Institute of Technology, Institute for Applied Materials – Ceramic Materials and Technologies, Germany

The two prototype perovskites barium titanate and strontium tita-nate exhibit abnormal grain growth properties during sintering. While they are similar in many properties, one important differ-ence between them is their defect chemical behaviour: while in strontium titanate Ti vacancies play no role, they are the dominant vacancies in barium titanate. The defect chemistry impacts sintering in many different ways. For example the grain boundary energy and its anisotropy strongly depend on the vacancy concentration. The grain boundary mobility is impacted by the segregation of defects (space charge). Due to the different cation vacancies, stoi-chiometry and second phases are important as well. This study highlights that grain growth of the system barium strontium tita-nate can be well understood in terms of defect chemistry. Grain growth in bulk polycrystals was observed to quantify bimodal grain growth. It is found that the bimodality (difference between large and small grains) is much stronger on the Ba-rich side. To observe the impact of local microstructure and faceting, ex-situ grain growth at polycrystalline surfaces was observed with SEM and EBSD. In these studies, the impact of local misorientation becomes visible. Overall, the defect chemical properties (stoichiometry and second phases, sintering atmosphere as well as temperature etc.) strongly influence – if not cause – these growth anomalies.

11:45 AM(EAM-BASIC-S5-006-2018) The Influence of Impurities and Second Phase Particles on the Microstructural Evolution of AluminaR. Moshe*1; W. D. Kaplan1

1. Technion - Israel Institute of Technology, Israel

The microstructure of a sintered body strongly depends on the composition of the powder used for the sintering process, where dopants and impurities are known to affect sintering and grain growth. In addition, second phase particles are also known as grain growth inhibiters, inducing Zener drag on the grain boundaries. In this study, nickel alumina nanocomposites were doped with CaO at a concentration below the solubility limit. Unlike segregating dopants which reduce grain boundary mobility by solute-drag, CaO increases the rate of grain growth. The goal of this study was to understand the influence of Ni particles on the increased grain boundary mobility (due to CaO) and microstructural evolution of alumina. The amount of CaO in the alumina was determined by conducting fully standardized wavelength dispersive spectroscopy (WDS) and the change in grain boundary mobility was characterized using scanning electron microscopy.

12:00 PM(EAM-BASIC-S5-007-2018) Surface Faceting of Barium Strontium Titanate AlloysM. J. Michie*1; F. J. Altermann2; W. Rheinheimer2; C. Handwerker1; J. Blendell1

1. Purdue University, Materials Engineering, USA2. Karlsruhe Institute of Technology, Germany

The effect of alloying barium titanate (BTO) with strontium tita-nate (STO) on grain growth is being investigated. In this study, it is proposed that there are transitions in relative grain boundary energies with temperature that create the non-Arrhenius grain growth behavior widely observed for STO and that those transitions in grain boundary energy are reflected in changes in Wulff shape. In this talk, the transitions in Wulff shape will be reported for the isomorphous BTO/STO system as a function of composition and


Abstracts

temperature by measuring equilibrium pore shapes inside grains and surface facets on sintered samples. The pore shapes determined by SEM and surface faceting determined by AFM are presented for three different compositions ratios: 25:75, 50:50 and 75:25 Ba:Sr and compared with previous results in STO. In particular, surface facets after long-term annealing at various temperatures have been studied to investigate prior reports of “microfacetted” regions in STO that develop in pores between the highly stable low index facets, (100), (110) and (111). The implications of the observed transitions and microfaceting behavior on grain boundary energies and grain growth in BTO/STO will be discussed.

ELECTRONICS DIV S2: Energy Applications of Electronic and Ferroic Ceramics: Synthesis, Characterization, and Theory

Energy Applications of Electronic and Ferroic CeramicsRoom: Citrus BSession Chair: Paul Evans, University of Wisconsin

10:00 AM(EAM-ELEC-S2-001-2018) Flexocaloric Response of Epitaxial Ferroelectric Films (Invited)H. Khassaf1; T. Patel*1; R. Hebert1; P. Alpay1

1. University of Connecticut, Materials Science and Engineering, USA

The flexoelectric effect in dielectric materials generates an electric polarization as a result of strain gradient. Here we show that the flex-oelectric response also produces a flexocaloric adiabatic temperature variation in heteroepitaxial ferroelectric films that are either partially or completely relaxed. The flexocaloric temperature change of (001) BaTiO3 films on (001) SrTiO3 substrates are computed as a func-tion of film thickness and temperature. Our calculations predict that a flexocaloric temperature change of 0.49 °C can be realized in 20 nm thick epitaxial BaTiO3 films, which is comparable to the intrinsic electrocaloric response of 0.75°C for bulk, single-crystal BaTiO3 at 25 oC and applied electric field of 200 kV/cm. This demonstrates that the flexocaloric response can be on par with elec-trocaloric temperature changes in thin film ferroelectrics and may play an important role in potential applications such as on-chip solid-state cooling.

10:30 AM(EAM-ELEC-S2-002-2018) NSMM Modeling and Design of Energy Conversion MaterialsS. Tidrow*1

1. Alfred University, USA

Through comparing the room temperature structure, lattice param-eter and volume of roughly 100 perovskite materials, we numerically reiterate the significant improvement in modeling performance that the temperature dependent new simple material model (NSMM) provides over Goldschmidt’s tolerance factor formalism (GTFF). Further, NSMM maintains such enhanced performance over extended temperature ranges, roughly 100 K to near the melting temperature of the material. Although NSMM is based on many of the same historical constructs as GTFF, physical constraints of NSMM overcome Goldschmidt’s tolerance factor, a correla-tion relation. The physical constraints are used for development of temperature dependent ionic radii, which are used in conjunction with the Clausius – Mossotti relation for development of coordina-tion and temperature ionic polarizability. Combined, coordination and temperature dependent genome-like ion properties, radii and polarizability, can be used to determine a wide range of tempera-ture dependent material properties, including but not limited to

crystal structure, lattice parameter and volume, relative permittivity, polarization induced structural phase transition temperature, and, volume induced structural phase transition temperature. NSMM constructs are leading to discovery and improved understanding and development of novel energy conversion materials and devices.

10:45 AM(EAM-ELEC-S2-003-2018) Electrocaloric effects in Pb(Nb,Zr,Sn,Ti)O3 ceramics near ferroelectric and antiferroelectric phase transitionsT. Usui*1; S. Hirose1; X. Moya2; N. D. Mathur2

1. Murata Manufacturing Co., Ltd., Japan2. University of Cambridge, United Kingdom

Electrocaloric (EC) effects are nominally reversible thermal changes that arise in electrically polarisable materials when subjected to changes in electric field. EC effects are largest near ferroelectric and antiferroelectric phase transitions, and they have been suggested for next-generation solid-state cooling systems. Here we describe the EC performance of multilayer ceramic capacitors (MLCCs) that are based on Pb0.99 Nb0.02 [(Zr1-xSnx)1-yTiy]0.98O3 ceramics. Our newly fabricated MLCCs are attractive because they show both ferroelectric and antiferroelectric phase transitions, thus offering giant EC effects over a wide range of operating temperatures. For the x = 0.5 and y = 0.05 sample, we were able to shift the antiferroelectric phase transition below room temperature, and this led to a wide EC oper-ating temperature range of ~100 K. For the x = 0.7 and y = 0.09 sample, we were able to merge the ferroelectric and antiferroelectric phase transitions, and this led to a giant EC response of ~4.6 K for 18 MV m-1, at 428 K. Our results show that careful chemical tuning of ferroelectric and antiferroelectric oxides is a useful tool for the optimisation of EC effects.

11:00 AM(EAM-ELEC-S2-004-2018) Local electronic structure and covalent character in TiO2 and BCZT electroceramics by core-hole spectroscopies.G. M. Herrera*1; O. Solis2; A. Reyes-Rojas3; L. Fuentes-Cobas3

1. CONACyT-CIMAV, Physics of Materials, Mexico2. CIMAV, Nanotech, Mexico3. CIMAV, Physics of Materials, Mexico

It is well known that presence of covalent character (p-d hybrid-ization) in metal-transition compounds such as TiO2 that shows a rutile structure with tetragonal phase (P42/mnm) and Barium titanate doped with Calcium and Zirconium (BCZT) that shows a perovskite structure with tetragonal phase (P4mm) is related to the spontaneous polarization in both compounds. The purpose of this work is to determine the charge transfer parameters using the multiplet calculation to analyze the electronic structure in the BCZT. X-ray absorption spectroscopy (XAS) in combination with multiplet calculation for the L2,3 of Titanium (Ti) were performed using synchrotron radiation as a reference compound. The charge transfer parameters such as charge transfer energy Δ=4.0 eV and the 3d-3d correlation energy Udd=4.5 eV for TiO2 are in agreement with previous results reported in the literature. Following this procedure, electron energy loss spectroscopy in scanning transmission elec-tron microscopy (EELS-TEM) mode was performed through the L2,3 edge for Ti in the BCZT electroceramic. The theoretical analysis for BCZT compound that include the charge transfer effects shows an important presence of the covalent character (60%). Electron density distributions for tetragonal BCZT in the (001) plane and in the (002) plane were obtained by G-Fourier program complementing the structural analysis.


Abstracts

11:15 AM(EAM-ELEC-S2-005-2018) The kinetics and grain orientation dependence of the electric field induced phase transition in Sm modified BiFeO3 ceramicsJ. Ormstrup*1; M. Makarovic2; M. Majkut3; T. Rojac2; J. Walker4; H. W. Simons1

1. Technical University of Denmark, Physics, Denmark2. Jozef Stefan Institute, Electronic Ceramics, Slovenia3. ESRF, France4. Materials Research Institute, USA

Samarium-modified bismuth ferrite (BSFO) is a room-temperature multiferroic with a morphotropic phase boundary at 15.5 mol% Sm, where ferroelectric, antiferroelectric and paraelectric phases coexist, and the electromechanical response (Smax and d33) is maximized. Recently, an electric field induced phase transition was also discov-ered, which is believed to play a significant role in the macroscopic response. However, neither the kinetics nor the structural pathway for the transition are well understood. We used in-situ synchrotron x-ray powder diffraction to directly measure this transformation in real time within bulk ceramics. Our results show that only the antiferroelectric phase transforms; the paraelectric phase does not appear to participate. Furthermore, the transformation occurs pref-erentially in grains oriented parallel with the electric field, and with extremely slow kinetics. Remarkably, we estimate a time constant of 10 minutes for this transformation - orders of magnitude longer than other ferroelectrics (e.g. BNT-BT). These findings pave the way for better BSFO, pointing to texturing and the elimination of the paraelectric phase to enhance the electromechanical response. Moreover, they provide a detailed picture of the transformation kinetics and a greater understanding of electric field induced trans-formations in ferroelectric ceramics.

11:30 AM(EAM-ELEC-S2-006-2018) Magnetoelectric vibrational energy harvesters utilizing a phase transitional approachM. Staruch1; J. Yoo2; N. Jones2; P. Finkel*1

1. U.S. Naval Research Laboratory, USA2. Naval Surface Warfare Center Carderock Division, USA

Magnetoelectric hybrid energy harvesters, consisting of magne-tostrictive FeGa (Galfenol) and single crystal relaxor ferroelectric PIN-PMN-PT, have been studied and designed. An oscillating magnetic field produced from either vibrational or rotational motion is translated into a strain in the Galfenol. This strain is then transmitted to the piezocrystal, triggering an induced rhombohedral to orthorhombic phase transition in the (011) domain engineered PIN-PMN-PT crystal. Since this is a threshold phenomenon, the large jump in polarization produces an output voltage that is inde-pendent of frequency making this broadband energy harvesting device of interest for a wide range of non-resonant applications. A combination of modeling and component testing was performed, and a final device was realized. The models as well as the output of the harvester will be presented.

11:45 AM(EAM-ELEC-S2-007-2018) Time Resolved Neutron Single Crystal Diffraction: A Technique to Probe Polarization Switching in Organic FerroelectricsC. Fancher*1; A. Schultz2; C. Hoffmann1; X. Wang1

1. Oak Ridge National Lab, USA2. Argonne National Lab, USA

Organic electronics are attractive due to their light-weight, low cost, flexibility and environmentally benign properties. Applications currently range from photoelectric cells to organic light emitting diodes (OLED) phones and TV screens, and to non-volatile ferro-electric memory. Organic ferroelectrics have been hypothesized to involve proton transfer when the polarization is switched, limiting

the use of X-ray tools. In this paper, we present recent work on devel-opment of time-resolved single crystal neutron diffraction at the Spallation Neutron Source at the Oak Ridge National Laboratory. The electric-field setup was first demonstrated by observing domain reorientation and lattice strain in BaTiO3. The setup was then used to investigate the role of proton transfer as the mechanism of polarization switching in the molecular ferroelectric materials potassium dihy-drogen phosphate (KDP) and 2-phenylmalondialdehyde PhMDA.

12:00 PM(EAM-ELEC-S2-008-2018) Growth of orientation-controlled epitaxial (K, Na)NbO3 thick films and their ferroelectric and piezoelectric propertiesY. Ito*1; A. Tateyama1; Y. Nakamura1; T. Shimizu1; M. Kurosawa1; H. Funakubo1; H. Uchida2; T. Shiraishi3; T. Kiguchi3; T. J. Konno3; M. Ishikawa4

1. Tokyo Institute of Technology, Japan2. Sophia University, Japan3. Tohoku University, Japan4. Toin University of Yokohama, Japan

Films of lead free piezoelectric materials have attracted much atten-tion for various devices. (K, Na)NbO3 is known to show a relatively large piezoelectric response among the lead-free piezoelectric mate-rials. Hydrothermal method is a low temperature process that can avoid the vaporization of Na and K from (K, Na)NbO3. Our group already reported on the growth of orientation-controlled (K, Na)NbO3 films at 240°C by hydrothermal method using KOH, NaOH and Nb2O5 as source materials and their film thickness grown by hydrothermal method was above ten micrometer by one process. In this presentation, (100)c-, (110)c- and (111)c-oriented epitaxial (K, Na)NbO3 thick films were grown on (100)cSrRuO3//(100)SrTiO3, (110)cSrRuO3//(110)SrTiO3 and (111)cSrRuO3//(111)SrTiO3 substrates, respectively. These films showed characteristic surface morphologies. These morphology can be explained by the crystal facet of the initial nuclei on the surface of the substrate and the anisotropy of growth rates with respect to the crystal orientation. In addition, we report on orientation-controlled epitaxial (K, Na)NbO3 thick films of the piezoelectric properties as well as ferroelec-tric ones.

12:15 PM(EAM-ELEC-S2-009-2018) Study of Bonding Material Utilizing Cold Sintering for High-Temperature Energy Harvesting Piezoelectric DeviceW. Chen*2; A. Gurdal3; S. Tuncdemir3; J. Guo2; C. Randall1

1. Pennsylvania State University, Materials Science and Engineering, USA2. Pennsylvania State University, Material Research Institute, USA3. Solid State Ceramics, Inc, USA

Among the peripheral sensors in engine modules, energy harvesting piezoelectric devices have to withstand higher temperatures expected to be at least 350 οC. However, the use of resin protective bonding, FR4 substrates, and Sn-Ag solders in current devices limit their use in such high temperatures. Previously, we presented a promising new bonding technique that enables the joining of different mate-rials at low temperatures and provides a bond superior to that of polymer adhesives at high temperatures, in the temperature range of 250°C to 500°C. This technique involves a low temperature sintering process that is termed “Cold Sintering Process(CSP)”. Although the high temperature bonding result of CSP is promising, further enhancement is required to base on aspect of device design appli-cable for high temperature vibration. Here, we report the effect of various bonding materials on the quality of bonding and the power output of device as function of temperature from room temperature to 350oC. Mechanical properties have been analyzed for each system and have been correlated with their power outputs. This compara-tive study of their high temperature vibration responses will enable us to focus on some important aspects that are essential to improve


Abstracts

electro-mechanical properties in future higher temperature energy harvesting piezoelectric systems.


Electronics Materials for 5G Telecommunications Applications IRoom: Magnolia A/BSession Chairs: Nate Orloff, NIST; Geoff Brennecka, Colorado School of Mines

10:00 AM(EAM-ELEC-S6-001-2018) What is 5G and how can materials help?N. Orloff*3; C. Long2; G. L. Brennecka1

1. Colorado School of Mines, USA2. NIST, USA3. National Institute of Standards and Technology, Communications

Technology Laboratory, USA

Demand for mobile data, the implementation of new wireless devices, and an explosion of mobile users has stressed our current telecommunications infrastructure to its limits. In response to this demand, the Federal Communications Commission released new bands for telecommunications above 28 GHz, commonly referred to as 5G. Meanwhile, engineers have pushed many existing devices to the limit of their operating frequencies, and must now design new architectures to work at these new bands. These same architectures must also work with more complicated channel access methods to address this multifaceted capacity and application problem. With the urgency to capitalize on these new bands and evolution of frequency agile components, there is a growing clamor that conventional mate-rials are not up to the challenge. Hence, materials science engineers have an opportunity to develop new materials that answer the call of 5G. In this presentation, I will introduce 5G, discuss how modern transceivers work, and most importantly how materials can help.

10:15 AM(EAM-ELEC-S6-002-2018) Bulk Acoustic Wave (BAW) RF filters for 5th Generation Telecommunication (Invited)R. Aigner*1

1. Qorvo, Acoustic R&D, USA

BAW filters are an essential ingredient for or 4th generation LTE handheld devices. They and produced in quantities exceeding 10 billion units per year. The demand for larger data rates and shorter latency times forces 5th generation devices to work at frequencies exceeding the current technology limitations of acoustic RF filter technologies. Large data rates require wider spectrum allo-cations and accordingly filters with larger bandwidth than current generation BAW filters offer. The presentation will discuss the chal-lenges of BAW for frequencies above 5 GHz with respect to materials and processes used. New materials and enhanced process technology will be key to serve this emerging market.

10:45 AM(EAM-ELEC-S6-003-2018) Tunable and Switchable RF blocks Based on Barium Strontium Titanate Films (Invited)T. S. Kalkur*1

1. University of Colorado Colorado Springs, Electrical and Computer Engineering, USA

Modern cell phones need large number of resonators, filters and duplexers for wireless communications. Barium Strontium Titanate films have been investigated as tunable materials for a variety of

RF applications such as tunable filters, matching networks and antennas. Bulk acoustic wave devices based on piezoelectric thin films give the opportunity to fabricate these devices which are of small size. Currently Aluminum Nitride is the most common piezo-electric thin film used for these applications. Recently, BST thin films have been investigated since they offer the unique opportunity to fabricate switchable and tunable bulk acoustic wave devices because of their voltage dependent piezoelectric effect. In this presentation, we will review the status of the design, simulation, fabrication and characterization of a variety of BST based tunable RF blocks as well as switchable bulk acoustic wave devices such as resonators, band pass and band stop filters and duplexers. These bulk acoustic devices are solidly mounted on silicon or sapphire wafers with Bragg Reflectors to minimize the attenuation of acoustic waves. We will also discuss various material combinations that can be used for the fabrication of Bragg Reflectors that can withstand the BST thin film processing conditions.

11:15 AM(EAM-ELEC-S6-004-2018) mm-Wave dielectric property study of glass and ceramics (Invited)L. Cai*1

1. Corning Incorporated, Science and Technology, USA

The advent of 5G communication has instigated interests among material scientists to develop new materials that show excellent electrical properties at high frequencies. In the world of passive electronic components, the main consideration is to minimize EM absorption in the mm-wave range, or in terms of material prop-erty, the lowering of loss tangent. While some composite materials have been developed for specific high frequency applications, there is very little work has been done to enhance the electrical property performance for homogeneous inorganic materials. Here we present on-going work of characterization of dielectric property of glass and related materials. We show that for some glass compositions the dielectric behavior at higher frequencies can be surprisingly different from their low frequency counterpart. In other materials such as glass-ceramics, we show that how the ceramming process can change the dielectric property based on final crystalline phases and residual glass composition. The study offers insights on how to enhance the high frequency performance of solid amorphous materials that can be compatible with modern day manufacturing process.

11:45 AM(EAM-ELEC-S6-005-2018) How to Measure Relative Permittivity of Thin-Films and Substrates from 100 Hz to 125 GHzE. Marksz*1; N. Orloff2; A. Hagerstrom2; C. Long2; J. Booth2; I. Takeuchi1

1. University of Maryland, Materials Science And Engineering, USA2. National Institute of Standards and Technology, Communications

Technology Laboratory (CTL), USA

The 5G network will employ wireless spectrum ranging up into the tens of GHz. Novel electronic materials with efficient (low-loss) and advantageous (high dielectric constant) properties at high frequen-cies are crucial for devices operating on such a network. Scientists are synthesizing new dielectric compounds to fill this role at a rapid pace, creating the need for a quick, standardized metrology technique. We explain in detail a broadband, complex permittivity characteri-zation approach that provides an accurate method for determining materials behavior and understanding the underlying physical phenomena up to 125 GHz. This on-wafer technique uses a cali-bration-comparison approach to extract the frequency-dependent capacitance and conductance of identical interdigitated capacitors (IDC) and co-planar waveguides (CPW) fabricated directly on a thin-film sample and a reference substrate. We then use finite- element models to extract values for the relative permittivity that are consistent between devices. We demonstrate this measurement technique with well-studied materials, and provide insight in deter-mining and mitigating the uncertainty of our results.


Abstracts

12:00 PM(EAM-ELEC-S6-006-2018) PZT Based RF MEMS for Military and 5G Telecommunications Applications (Invited)J. Pulskamp*1; S. Bedair1; R. Rudy1; R. Benoit1; D. M. Potrepka1; R. G. Polcawich2

1. U.S. Army Research Laboratory, Sensors & Electron Devices Directorate, USA

2. US Army Research Laboratory, USA

This presentation will discuss several key materials and process considerations and highlight the performance of MEMS-based radio frequency (RF) devices for use in military and commercial systems with a focus on variable capacitors, tunable inductors, and RF switches. The integration of lead zirconate titanate (PZT) thin films and low-loss multi-layer metal MEMS structures enables a wide array of high performance RF devices applicable to 5G tele-communications as well as military tactical radios and radar systems. Critical process and design considerations including the mitigation of residual stress deformation, achieving electrode and piezoelec-tric material texture control, and the integration of PZT thin film processing with multilayer metal processing will be discussed. The technology has enabled PZT RF MEMS variable capacitors with demonstrated analog capacitance ratio tuning of >40:1, peak Quality factors exceeding 800 at frequencies >1 GHz, and self-resonance frequencies >40GHz. Extremely tunable inductors have also shown tuning ratios in excess of 4:1 in the range of a few GHz. Static high-Q inductors, monolithically integrated with these devices have shown Quality factors as high as 220. PZT actuated RF switches and relays have demonstrated operating voltages as low as a few volts while providing isolation better than -50 dB and insertion loss better than 0.3 dB from DC to 6 GHz.


Pioneers in SynthesisRoom: Cypress A/BSession Chairs: Jon-Paul Maria, North Carolina State University; Elizabeth Paisley, Sandia National Laboratories

10:00 AM(EAM-ELEC-S10-001-2018) The Good, The Bad, and The Ugly – Redefining the Role of Defects in Complex-Oxide Thin Films (Invited)L. W. Martin*1

1. University of California, Berkeley, Materials Science and Engineering, USA

Our ability to manipulate and control complex materials remains rudimentary as compared to the precise control of materials demon-strated in other fields (e.g., the ppb-level control of defects in traditional semiconductor materials). Although modern approaches to epitaxial thin-film growth have enabled unprecedented control of single/multi-layer systems, emergent physical phenomena, and advances in our fundamental understanding of complex oxides, controlling defects at even the 0.1-1% level is challenging. In turn, defects (i.e., intrinsic or extrinsic in nature) play a critical role in the evolution of properties and phenomena. Here, we will explore our limitations in producing complex-oxide materials with the level of control we desire to have, what those limitations mean for understanding and utilizing these materials, and the opportuni-ties for embracing these defects as a new design parameter. We will call upon examples of processing-defect-property relationships in a range of epitaxial thin-film materials including SrTiO3, LaAlO3, NdNiO3, BaTiO3, PbTiO3, BiFeO3, and others. We will highlight how

synthesis determines defect structures, how epitaxy can influence defect formation/ordering, how the defects influence properties, how to probe and study such defects, and how to deterministically produce defects in a way that enhances or improves performance.

10:30 AM(EAM-ELEC-S10-002-2018) Electronic Transport and Ferroelectric Switching in Ion-Bombarded, Defect-Engineered BiFeO3 Thin FilmsS. Saremi*1; R. Xu1; L. Dedon1; R. Gao1; L. W. Martin1


Despite continued interest in thin films of the multiferroic BiFeO3, deterministic control of this material has remained a challenge due to the complex nature of its chemistry and penchant for defects. In this work, we show that high-energy ion bombardment can be a valuable technique for tuning the concentration of intrinsic defects, and provides a route to a systematic study of defect-property rela-tions in ferroelectric thin films. We also demonstrate the potential of ion bombardment for property enhancement, including multiple orders of magnitude enhancement in electrical resistivity and improvement of ferroelectric hysteresis responses. In particular, we will show that the high leakage in as-grown BiFeO3 thin films is due to the presence of moderately shallow isolated trap states. Ion bombardment is shown to be an effective way to reduce this free carrier transport by trapping the charge carriers deep in the band gap as a result of the formation of bombardment-induced deep-lying defect complexes and clusters. The ion bombardment, is also found to give rise to a systematic increase in the coercivity, an extension of defect-related creep regime, an increase in the pinning activation energy, a decrease in the switching speed, and a broadening of the field distribution of switching, as a result of an increase in defect concentration.

10:45 AM(EAM-ELEC-S10-003-2018) Reliability of Piezoelectric Microelectromechanical Systems (Invited)S. Trolier-McKinstry*1


Utilization of piezoelectric microelectromechanical systems incorpo-rating high strain piezoelectric films such as lead zirconate titanate, PZT, or sodium potassium niobate, KNN, requires an understanding of the factors that will govern the electrical and mechanical reliability under the high electrical and strain fields important in applications. It is found that the processing conditions utilized for preparation of these films has a profound influence on the measured reliability, even in films that all have ostensibly the same levels of phase purity, crystallographic orientation, and composition. In PZT films, the presence of small amounts of excess PbO which segregates to columnar grain boundaries significantly reduces the DC breakdown field and the activation energy for failure via resistance degradation, while increasing the density of cracking induced by piezoelectric strain, and the density of thermal breakdown events. For {100} oriented PZT films, failure is often initiated by cracking, followed by thermal breakdown events. Thicker films build up the critical stress required for failure at lower electric fields; it appears that the critical stress for failure is ~ 500 MPa. Commercially available KNN films show a strong voltage and temperature dependence to failure, and as a result, are likely to be limited to somewhat lower drive fields than PZT films.


Abstracts

11:15 AM(EAM-ELEC-S10-004-2018) Understanding the defect chemistry controlling DC resistance degradation in PZT filmsB. Akkopru Akgun*1; T. J. Bayer1; K. Tsuji1; C. Randall1; M. Lanagan2; S. Trolier-McKinstry1

1. Pennsylvania State University, Materials Science and Engineering, USA2. Pennsylvania State University, Engineering Science and Mechanics, USA

One of the keys for development of piezoelectric (PZT) based MEMS devices is understanding the defect chemistry controlling the reliability and life-time, which is limited by the voltage-induced resistance degradation process. Under simultaneous temperature and dc field stress, oxygen vacancies drift and eventually pile up at the cathode, which leads to subsequent generation of electrons and holes in positive-biased and negative-biased regions, respectively. The objective of this study is to understand the difference in resis-tance degradation behavior between acceptor (Mn) and donor (Nb) doped PZT films. Thermally Stimulated Depolarization Current (TSDC), Impedance and Deep Level Transient Spectroscopy (DLTS) measurements were conducted to understand the difference in the conduction mechanism leading to resistance degradation in PMZT and PNZT films. Although the initial conductivity of PNZT film is lower than their Mn doped counterparts, PNZT film showed higher degradation rates. The increase in an electron/hole trapping effect due to multivalent nature of Mn explains the difference in degra-dation behavior of PNZT and PMZT films. Calculated activation energies from DLTS and impedance data revealed that hole hopping between Pb2+ and Pb3+ and electron trapping by Ti4+ are two main reactions that governs the degradation process in PZT films.

11:30 AM(EAM-ELEC-S10-005-2018) Nucleation Studies of In-situ Sputtered Lead Zirconate Titanate Thin FilmsC. Y. Cheng*1; K. Grove2; B. Gibbons2; R. Benoit3; D. M. Potrepka3; J. Mulcahy3; G. R. Fox4; R. G. Polcawich5; S. Trolier-McKinstry1

1. Pennsylvania State University, Materials Science and Engineering, USA2. Oregon State University, School of Mechanical, Industrial, and

Mechanical Engineering, USA3. US Army Research Laboratory, Sensors and Electron Devices

Directorate, USA4. Fox Materials Consulting, LLC, USA5. Defense Advanced Research Projects Agency, USA

Various bottom electrodes and lead zirconate titanate (PZT) thin films were grown on thermally oxidized silicon substrates via in-situ sputtering without breaking vacuum. While preferred {001} orienta-tion PZT was achieved, an impurity phase suggested to be massicot was also observed. It was found that the nucleation step, rather than the bulk PZT deposition step, was critical in minimizing secondary phases. In addition, the type of bottom electrode used dictated the preferred crystallographic orientation of PZT. For instance, for plat-inum bottom electrodes grown in-situ, the following nucleation layers had an XRD peak intensity ratio of greater than 1 for {001} PZT relative to the impurity phase. Such samples required at least a thin layer of titanium annealed in a lead-rich environment to yield {001} PZT, although this still yielded a small amount of massicot. For platinum bottom electrodes not grown in-situ, nucleation layers formed with little {001} PZT and the growth of platelets suggested to be {111}-oriented massicot were observed. Preliminary data indi-cated that iridium oxide bottom electrodes grown in-situ yielded {001} and {101} PZT and little massicot phase even without any seed layer deposition. The importance of a Ti layer deposited on top of the bottom electrode for PZT nucleation and growth in a lead rich environment will be discussed.

11:45 AM(EAM-ELEC-S10-006-2018) Investigating the Dynamic Evolution of Ceramic Materials in Energy Storage Systems (Invited)M. McDowell*1; F. J. Quintero Cortes2

1. Georgia Institute of Technology, Mechanical Engineering, Materials Science and Engineering, USA

2. Georgia Institute of Technology, Materials Science and Engineering, USA

In energy storage devices, as-synthesized ceramic materials evolve from their initial state either due to electrochemical reactions or interfacial instabilities at interfaces, and such transformations must be understood and controlled for improved electrochemical behavior. In my group, multiscale in situ techniques are used to reveal reaction mechanisms, degradation processes, and interfacial transformations in energy storage materials to guide the develop-ment of better batteries. Our recent work has used a combination of in situ transmission electron microscopy (TEM), in situ x-ray diffraction/spectroscopy, and operando x-ray imaging methods to i) elucidate phase transformation pathways in high capacity elec-trode materials and ii) understand interfacial dynamics in ceramic electrolyte materials. For instance, both Cu2S and FeS2 electrode materials show similar global transformations during reaction with alkali metal ions, but the nanoscale reaction pathways differ signifi-cantly, which influences the electrochemical behavior. Additional research focused on using operando X-ray methods to measure strain evolution in battery electrode materials will also be presented. These results demonstrate the importance of utilizing in situ tech-niques to understand dynamic processes in energy materials so as to guide the synthesis of new materials with high energy density and long lifetime.


Superconducting Materials IRoom: Citrus ASession Chair: Gang Wang, Institute of Physics, Chinese Academy of Sciences

10:00 AM(EAM-ELEC-S11-001-2018) Electronic nematicity in a copper oxide superconductor (Invited)J. Wu*1

1. Brookhaven National Laboratory, Condensed Matter Physics, USA

Over the course of extensive experimental studies of La2-xSrxCuO4 films synthesized by molecular beam epitaxy, we discovered that a spontaneous voltage develops across the sample, transverse to the electrical current. This unusual metallic state, in which the rotational symmetry of the electron fluid is spontaneously broken, occurs in a large temperature and doping region. The superconducting state always emerges out of this nematic metal state.

10:30 AM(EAM-ELEC-S11-002-2018) Single Crystal Growth and Doping of Possible Chromium Analogues to Fe-based SuperconductorsM. A. Susner*2; R. Jishi2; J. Rodriguez2; T. Bullard3; T. J. Haugan1

1. Air Force Research Lab, AFRL/RQQM, USA2. California State University, Los Angeles, Department of Physics and

Astronomy, USA3. Air Force Research Lab, Aerospace Systems Directorate, USA

Recent theoretical predictions have suggested that the band struc-ture of BaCr2As2 is similar to the parent BaFe2As2 phase in such a way that doping that compresses the lattice and/or donates electrons to the may induce a superconducting ground state. We at AFRL have successfully grown both the antiferromagnetic parent phase


Abstracts

BaCr2As2 compound and its doped daughters in single crystal form. Both the Ba(Cr1-xNix)2As2 and the Ba(Cr1-xCox)2As2 systems were found to be fully miscible. These doped materials were character-ized in terms of their fundamental magnetic, electrical, structural, and thermodynamic properties in a search for superconductivity. Correlations were made between these properties. Density func-tional theory is used to explain the properties we measure in terms of the electronic structure of the material and its evolution with doping.

10:45 AM(EAM-ELEC-S11-003-2018) Phase diagram of single-crystalline Eu(Fe1-xCox)2As2 (x ≤ 0.24) grown by transition metal arsenide fluxG. Wang*1; W. R. Meier2; W. E. Straszheim3; J. Slagle2; S. Bud’ko2; P. C. Caneld2

1. Institute of Physics, Chinese Academy of Sciences, China2. Ames Laboratory, Iowa State University, USA3. Civil and Construction Engineering Department, Iowa State University,

USA

Interplay of magnetism and superconductivity (SC) has been a focus of interest in condensed matter physics over several decades. EuFe2As2 has been identified as a potential platform to investigate interactions between structural, magnetic, electronic effects and coexistence of magnetism and SC at similar temperatures. However, there are obvious inconsistencies in the reported phase diagrams of Eu(Fe1-xCox)2As2 crystals grown by different methods. For transi-tion metal arsenide (TMA)-flux-grown crystals, even the existence of SC is open for dispute. Here we re-examine the phase diagram of single-crystalline Eu(Fe1-xCox)2As2 grown by TMA flux. We found that the lattice parameter c shrinks linearly with Co doping, almost twice as fast as that of the tin-flux-grown crystals. With Co doping, the spin-density-wave (SDW) order of Fe is quickly suppressed, being detected only up to x = 0.08. The magnetic ordering tempera-ture of the Eu2+ sublattice (TEu) shows a systematic evolution with Co doping, first goes down and reaches a minimum at x = 0.08, then increases continuously up to x = 0.24. A new magnetic feature is observed at temperatures below TEu. Over the whole composition range investigated, no signature of SC is observed.

11:00 AM(EAM-ELEC-S11-004-2018) Large negative magnetoresistance of a nearly Dirac material EuMnSb2 (Invited)K. Yamaura*1

1. National Institute for Materials Science, Japan

Single crystals of EuMnSb2 were successfully grown for the first time (Fig. 1), and their structural and electronic properties were investigated systematically. The material crystallizes in an orthor-hombic-layered structure (space group: Pnma) comprising a periodic sequence of –MnSb/ Eu/ Sb/ Eu/– layers (~1 nm in thick-ness) and massless fermions are expected to emerge in the Sb layer, by analogy of the candidate Dirac materials EuMnBi2 and AMnPn2 (A = Ca or Sr or Ba, Pn = Sb or Bi). The magnetic and specific heat measurements of EuMnSb2 suggest an antiferromagnetic ordering of Eu moments near 20 K. A characteristic hump appears in the temperature dependent electrical resistivity curve at ~25 K. A spin-flop transition of Eu moments with an onset magnetic fieldof ~15 kOe (at 2 K) was observed. Interestingly, EuMnSb2 shows a negative magnetoresistance (up to –95%) in contrast to the positive magnetoresistances observed for EuMnBi2andAMnPn2 (A = Ca or Sr or Ba, Pn = Sb or Bi), providing a unique opportunity to study the correlation between electronic and magnetic properties in this class of materials. * This study was conducted by a collaboration of Changjiang Yi,1 Shuai Yang,1 Meng Yang,1 Qiunan Xu,1 Le Wang,1 Yoshitaka Matsushita,2 Shanshan Miao,1 Yuanyuan Jiao,1 Hongming Weng,1 Jinguang Cheng,1 Yongqing Li,1 Kazunari Yamaura,2 Youguo Shi,1 Jianlin Luo 1; 1IOP/CAS, China; 2NIMS, Japan.

11:30 AM(EAM-ELEC-S11-005-2018) Thermal expansion and high magnetic field electrical transport measurements on Fe substituted URu2Si2 (Invited)S. Ran*1

1. University of Maryland, Material Science and Engineering, USA

The search for the order parameter of the hidden order (HO) phase in URu2Si2 has attracted an enormous amount of attention for the past three decades. The small antiferromagnetic moment found in the HO phase is too small to account for the entropy derived from the specific heat anomaly associated with the HO transition. Many studies suggest that the HO and a large moment antiferromagnetic (LMAFM) are intimately related and that a comprehensive inves-tigation of both phases will be useful in unraveling the nature of order parameter of the HO phase. We have recently demonstrated that tuning URu2Si2 by substitution of Fe for Ru offers an opportu-nity to study the HO and LMAFM phases at atmospheric pressure. Specifically, the substitution of the smaller Fe ions for Ru ions in URu2Si2 acts as a “chemical pressure” and reproduces the tempera-ture vs pressure phase diagram. Therefore, our results provide a unique opportunity to carry out ambient pressure experiments to study the LMAFM phase. Motivated by this observation, we performed thermal expansion measurements, as well as electrical resistivity measurements in high magnetic fields, on URu2-xFexSi2 single crystals in both the HO and LMAFM regions of the phase diagram. Interesting preliminary results have emerged from these studies that shed light on the LMAFM phase and its relationship with the elusive HO phase.

12:00 PM(EAM-ELEC-S11-006-2018) Carbon’s allotropy towards becoming the lightest magnetic superconductor (Invited)N. Gheorghiu*2; C. Ebbing3; T. J. Haugan1

1. Air Force Research Lab, AFRL/RQQM, USA2. UES, Inc., USA3. University of Dayton Research Institute, USA

The electromagnetic and exchange mechanisms antagonize super-conductivity and magnetism. Whether the two phenomena can coexist in the same material remains a central topic in condensed matter research. The focus of this study is to find whether magnetic superconductors can be found among certain carbon allotropes. We are probing magnetic and transport properties of various graphitic samples: carbon fibers, pyrolytic graphite, graphite foil, highly oriented pyrolytic graphite, natural graphite crystals, and high-quality graphite powder. Samples’ electronic properties were modified towards prevalent electron or hole conduction via processes such as oxygen-ion implantation or boron intercalation. Other samples were brought into contact with an alkane such as octane, where the self-assembly process leads to the free protonation of the graphite’s interfaces. PPMS magneto-transport and magneti-zation studies were conducted for temperatures in the range 1.9 K to 300 K and magnetic fields up to 9 T. We find evidence for the coexistence of room-temperature weak ferromagnetism and possible superconductivity located at graphite’s interfaces. The observed features are similar to the ones found in HTS granular superconduc-tors with Josephson-coupled grains. Acknowledgements: The Air Force Office of Scientific Research (AFOSR), The Aerospace Systems Directorate (AFRL/RQ), and United Energy Systems (UES, Inc.)


Abstracts

ELECTRONICS DIV S12: Thermal Transport and Storage in Functional Materials and Devices

Thermal Transport and StorageRoom: Orange DSession Chair: Alp Sehirlioglu, Case Western Reserve University

10:00 AM(EAM-ELEC-S12-001-2018) What is the likely value of the thermal conductivity of my ceramic material? (Invited)D. R. Clarke*1

1. Harvard University, School of Engineering and Applied Scieneces, USA

The thermal conductivity of ceramics probably span the largest range of any class of materials. Some, such as AlN and SiC, have exceptional conductivities that approach that of diamond whereas others, such as the ionic conductors and thermoelectrics, have very low values that approach those of dense polymers. Although the essential physics controlling thermal transport in materials is well understood, it is often extremely difficult to compute the rele-vant equations with sufficient precision to be useful. Nevertheless, considerable insight exists as to the likely values of the thermal conductivity based solely on knowledge of the crystal structure, the nature of the defects and their concentration. Also, in many mate-rials development and device programs, the thermal conductivity is one of several materials parameters that need to be optimized. For this reason, precise values are often not needed. In this presen-tation, simple guidelines will be presented for predicting the thermal conductivity of ceramics and the assessing materials design strate-gies that can be employed for selecting desirable microstructural and defects. Examples will be drawn from developments in ferroelectrics, thermoelectrics and thermal barrier coating materials.

10:30 AM(EAM-ELEC-S12-002-2018) Tuning Thermal Transport in Two-Dimensional Transition Metal DichalcogenidesL. Li*1

1. Boise State University, Micron School of Materials Science and Engineering, USA

Two-dimensional transition metal dichalcogenides (2D-TMDs) with the chemical formula MX2 (M = transition metal, X = chalcogen) are of great research interest due to their unique properties and poten-tial for materials-by-design applications in electronic and energy conversion applications. Having notable electrical, magnetic, optical, and thermoelectric properties, 2D-TMDs can be further tuned through substitutional dopants and heterojunctions. This presenta-tion will demonstrate our newly developed computational screening tool and strategy targeting TMD thermal management. We explored phonon–electron interaction, dopant and heterojunction effects on phonon scattering and thermal conductance. We also engineered the TMD materials for desired performance by tuning their phonon frequency gaps and transmission coefficients. Computational screening generated large and rich data sets to help us identify the relationships between the nature of transition metals and TMD properties. Our results facilitate TMD materials design.

10:45 AM(EAM-ELEC-S12-003-2018) Phonon Thermal Transport in Ultra-Wide Bandgap β-Ga2O3

B. Foley*1; S. Graham1

1. Georgia Institute of Technology, George W. Woodruff School of Mechanical Engineering, USA

Power electronic devices are critical components for the conver-sion and control of electrical power. While wide band gap materials

(GaN, SiC) have had a major impact by enabling the development of smaller and faster devices, researchers continue to seek disrup-tive improvements in power device performance. As a result, the so-called ultra-wide band gap (UWBG) semiconductors have entered the discussion with β-Ga2O3 emerging as an exciting candi-date. With a band gap of ~4.9 eV and easier to synthesize than AlN and Diamond, the figure of merit for β-Ga2O3 based devices exceeds that of commercially available 4H-SiC and GaN. Given these potential benefits of using β-Ga2O3 for power devices, the thermal conductivity of pure β-Ga2O3 is about an order of magnitude lower than both 4H-SiC and GaN, indicating that device self-heating may be the limiting factor when it comes to the power handling capa-bilities of these devices. Additionally, many characteristics of real devices (doping, defects, etc) will further impede phonon transport within the material. This presentation will focus on thermal trans-port in doped β-Ga2O3 single crystals along various crystallographic directions, as well as transport across metal/β-Ga2O3 heteroint-erfaces. The goal of this work is to provide researchers with new perspectives that promote a “thermal-first” approach to device design.

11:00 AM(EAM-ELEC-S12-004-2018) Characterization of thermal transport across cracks in optical materialsB. F. Donovan*2; J. LaFlam1; R. Warzoha1

1. United States Naval Academy, Mechanical Engineering, USA2. United States Naval Academy, Physics, USA

With the addition of directed energy and optical-based weaponry into the Navy’s fleet, the issue of operation of sensitive optics in extreme environments has become an area of increasing interest. In this work, we aim to identify potential sources of thermal buildup in optical materials (such as BK7 glass) that have been subjected to harsh environments. We aim specifically to characterize thermal transport across cracked glass materials and understand heat flow at glass-glass interfaces. This characterization will be conducted with a combination of thermoreflectance techniques, electro-thermal char-acterization, and scanning thermal microscopy.

11:15 AM(EAM-ELEC-S12-005-2018) Thermal conductivity mapping of iridium oxide using a combined non-contact and contact mode scanning hot probe techniqueA. A. Wilson*1; M. Rivas1

1. US Army Research Laboratory, Sensors and Electron Devices Directorate, USA

Iridium oxide has recently emerged as an appealing alternative to platinum as an electrode material for pyroelectric devices, demon-strating that the films may be grown in nano-platelet form. This increases surface area, effectively causing light trapping, which allows for control of photo-absorption at the film surface. However, very little information exists in the literature about the thermal properties of iridium oxide, and the roughness of these light-ab-sorbing films prohibits widely used thin-film thermal conductivity measurement techniques such as time- and frequency-domain thermoreflectance. Alternatively, the scanning hot probe (SHP) technique, based on scanning thermal microscopy, allows for local determination of material thermal conductivity with ultra-high resolution in the 10’s of nm, and may be used to characterize nano-platelets as well as dense films. This work discusses how the scanning hot probe technique may be used in a combination of contact mode and non-contact mode (to decouple parameters that often compromise the quantitative measurement capabilities of scanning thermal microscopy) in order to determine the thermal conductivity of both the dense and nanostructured films.


Abstracts

11:30 AM(EAM-ELEC-S12-006-2018) Characterizing Novel Transducers for High Temperature Thermal Measurements Using Time Domain ThermoreflectanceB. D. Butler*1; C. M. Rost1; J. L. Braun1; K. Ferri2; L. Backman3; C. Dawes2; T. M. Borman2; E. J. Opila3; J. Maria2; P. E. Hopkins1

1. University of Virginia, Mechanical and Aerospace Engineering, USA2. North Carolina State University, USA3. University of Virginia, Materials Science & Engineering, USA

Time domain thermoreflectance (TDTR) is an optical pump-probe technique used to measure thermal properties of material systems. Samples are typically coated with a thin metal transducer layer, such as aluminum or gold. At temperatures approaching 2,000°C, most transducers become limited by melting temperature, chem-ical reactions, or other phase transitions. Hafnium Nitride (HfN) is a conductive ceramic with a melting point exceeding 3300°C. It is estimated to have a constant reflectance of 17% and 64% at 400nm and 800nm, respectively. Iridium (Ir) has a melting temperature of 2,447°C. Our work characterizes the thermal properties of HfN and Ir, respectively, and investigates their viability as transducers for TDTR measurements at high temperatures to the point of thermo-dynamically-driven failure. Thermal conductivity is measured as a function of temperature for HfN and Ir, respectively, and ther-moreflectance coefficients are measured and compared to that of typical transducers. Thermal conductivities for MgO, Al2O3, SiO2, and diamond substrates are measured using the aforementioned thin films as transducers to test material reliability. Results and implications for future high temperature TDTR measurements are discussed. This work is supported by the U.S. Office of Naval Research MURI program (grant No. N00014-15- 1-2863).


Advanced Electronic Materials I: ProcessingRoom: Orange CSession Chairs: Satoshi Wada, University of Yamanashi; Matjaz Spreitzer, Jozef Stefan Institute

10:00 AM(EAM-ELEC-S13-001-2018) Strange Low Temperature Preparation of Perovskite-based Nano-complex Ceramics by Solvothermal Solidification Method (Invited)S. Wada*1

1. University of Yamanashi, Material Science and Technology, Japan

For next-generation material science, interface engineering is very key issue, and it can be expected that new phenomena and enhanced properties are originated from interface with structure gradient region. Recently, a new technique was proposed to prepare nano-structured ceramics with heteroepitaxial interfaces between barium titanate (BaTiO3, BT) and potassium niobate (KNbO3, KN) prepared at low temperatures below 300 deg. C, and their dielec-tric and piezoelectric properties were enhanced because of their heteroepitaxial interfaces. To explain the above results, we proposed the following hypothesis, i.e., KN had larger cell volume by 0.5 % than that of BT, and BT unit cell was expanded by epitaxial junc-tion with KN. To confirm the above idea, we prepared BT-KN nano-structured ceramics were prepared by solvothermal method in this study, and their dielectric properties were compared on the view of unit cell volume change of BT. After the reaction, the compacts were washed by ethanol, and dried at 200 deg. C.

10:30 AM(EAM-ELEC-S13-002-2018) Growth Peculiarities of Pb(Mg1/3Nb2/3)O3–PbTiO3 Epitaxial Thin Films on SrTiO3 Substrates Using Pulsed-Laser Deposition (Invited)M. Spreitzer*1; U. Gabor1; H. Uršič2; E. Tchernychova3; D. Suvorov1

1. Jozef Stefan Institute, Advanced Materials Department, Slovenia2. Jozef Stefan Institute, Electronic Ceramics Department, Slovenia3. National Institute of Chemistry, Department of Materials Chemistry,

Slovenia

The large number of adjustable parameters in pulsed-laser depo-sition technique enable the growth of high-quality thin films on various subsrates. In this study we systematically examined the influence of deposition parameters used to grow 0.67Pb(Mg1/3Nb2/3)O3–0.33PbTiO3 epitaxial thin films directly on SrTiO3 substrates to exploit the longitudinal (d33) energy-harvesting mode in piezo-electric micro-electro-mechanical systems. Our comprehensive approach enabled us to effectively control the phase composition of the films, involving the addition of 20 mol. % of PbO excess in order to achieve pyrochlore-free growth. Additionally, we showed that even in pyrochlore-free films the structure and performance of the films are strongly affected by the growth kinetics. Deposition in higher ambient pressure resulted in a lower density of anomalies in the film structure, yielding a twofold increase of the permittivity and enhanced local piezoelectric response. Our findings emphasize the importance of detailed structural analysis as a means of improving the electrical properties of thin films and provide a model for other multicomponent materials.

11:00 AM(EAM-ELEC-S13-003-2018) Utilizing Cold Sintering Process for the Fabrication of Microwave dielectric materials and devicesJ. Guo*1; N. Pfeiffenberger5; A. Baker1; H. Guo4; M. Lanagan2; C. Randall3

1. Pennsylvania State University, USA2. Pennsylvania State University, Dept. of Engineering Science and

Mechanics, USA3. Pennsylvania State University, Materials Science and Engineering, USA4. Pennsylvania State University, Materials Research Institute, USA5. SABIC, USA

High frequency dielectric materials are of interest for a wide variety of applications, such as, electronic packaging, substrates, and functional components including filters, baluns, couplers, antennas and metamaterials. According to the different sintering temperatures, typical dielectric ceramics are categorized into high temperature co-fired ceramics (HTCC), low temperature co-fired ceramics (LTCC) and ultra-low temperature co-fired ceramics (ULTCC). In the case of these three categorizes, the respec-tive sintering temperature ranges of ceramics are 1200-1800 °C, 900-1000 °C, and 400-700 °C, respectively. Recently, we developed a new sintering approach, namely “Cold Sintering Process” (CSP), which can enable densification at an extremely low tempera-ture (lower than 300 °C) with the assist of a transient liquid phase, such as water and acids. The low sintering temperature makes it possible to co-sinter thermoplastic polymers and ceramic materials in a one-step sintering process. In this work, CSP is introduced to fabricate microwave and packaging dielectric materials, including ceramics (bulk monolithic substrates and multilayers) and ceram-ic-polymer composites. Dense ceramics and composites with excellent dielectric properties were obtained by CSP at 120 °C, indicating that CSP provides an effective strategy for the ceramic packaging and microwave device development.


Abstracts

11:15 AM(EAM-ELEC-S13-004-2018) Low temperature sintering techniques: Paving the way to new ceramic materialsT. Herisson de Beauvoir*1; A. Ndayishimiye3; J. Guo2; Z. Xuetong1; G. Goglio3; C. Elissalde3; M. Josse3; C. Randall1

1. Material Research Institute - Pennsylvania State University, USA2. Pennsylvania State University, Materials Science and Engineering, USA3. ICMCB-CNRS, France

A huge activity on lowering the processing temperature of ceramics has been recently observed, more specifically about sintering step. Not only this allows for high economic impact for ceramic industry and a high improvement for environmental purpose through drastic energy savings, but it also opens new opportunities in terms of mate-rial design. Recent progress in Spark Plasma Sintering and Flash sintering, but also Hydrothermal Hot Pressing and the recent devel-opment of Cold Sintering Process brought sintering temperatures below 300 °C, down to ambient temperatures. As this new field is gaining more and more interest, new opportunities arose, leading to the design of ceramic-polymer type composites, or sintering molecular or even hydrated phase. The combination of both low sintering temperature and short sintering time lead to widening sintered materials scope and in some cases, preserve small grain sizes of nanometer scale. The aims of the present discussion are, in a first place, to highlight the various results observed using different sintering techniques (CSP, HHP, FAST, …), through comparative study allowing to identify similarities and discrepancies, and in a second place to give an overview of the actual new material’s devel-opment possibilities offered by such processes and their possible combination.

11:30 AM(EAM-ELEC-S13-005-2018) Freeze-Casting of High Temperature Dielectric CompositesE. Patterson*2; M. Baczkowski3; E. Gorzkowski1

1. Naval Research Lab, USA2. ASEE, USA3. University of Connecticut, USA

Freeze-casting has been used to construct ceramic-polymer compos-ites in which the two phases are arranged in an electrically parallel configuration. By doing so, the composites exhibit dielectric constant (K) up to two orders of magnitude higher than that of composites with ceramic particles randomly dispersed in a polymer matrix. In this study, the technique has been successful with aqueous slurries for a variety of pH values that were frozen uni-directionally to form templates such that ceramic aggregates are aligned in the tempera-ture gradient direction. Freeze-casting is a versatile processing technique that has been demonstrated to work with many ceramic systems. In this paper the continued study of freeze-cast processing of composites based around non-saturating Bi(Zn0.5Ti0.5)O3 – BaTiO3 ceramics for use in high power capacitor applications are discussed. Several processing parameters, including dispersant, choice of freeze-casting mold material, polymer composition, and slurry pH were examined. The various effects on the composite dielectric properties, polarization hysteresis, and composite microstructure will also be presented.

11:45 AM(EAM-ELEC-S13-006-2018) Dielectric and energy storage properties of Na(Nb1-xTax)O3 ceramics prepared by spark plasma sinteringJ. Bian*2; D. Suvorov1

1. Jozef Stefan Institute, Advanced Materials, Slovenia2. Shanghai University, Departemnt of Inorganic Materials, China

Na(Nb1-xTax)O3 (x=0.2,0.4,0.6,0.8) ceramics were prepared by spark plasma sintering (SPS). The structure and microstructure were char-acterized by XRD, SEM,TEM and XPS analysis. The dielectric and

energy storage properties were investigated by impedance analyzer and ferroelectric analyzer. Single phase and dense Na(Nb,Ta)O3 ceramics could be obtained by SPS. Reduction of Nb5+ was confirmed in Nb-rich compositions. The Tc temperature decreased with the increased of x. Weak double P-E loops could be observed for x=0.4 and x=0.6 compositions. The temperature dependent dielectric permittivity exhibited hysteresis for x=0.2 and x=0.4 compositions. The dielectric loss decreased with the increase of x. The energy storage properties were improved with the increase in Ta content. Maximum energy density of ~0.90 J/cm3could be obtained for x = 0.6 composition with the BDS of 159 kV/cm and efficiency of 87.5%.

12:00 PM(EAM-ELEC-S13-007-2018) Ceramics Intergranular Contacts in the Frame of Fractal HullV. Mitic*1; L. Kocic2; V. Paunovic2

1. Serbian Academy of Sciences, Institute of Technical Sciences, Serbia2. Faculty of Electronic Engineering, University of Nis, Serbia

Responsibility of intergranular contacts in ceramics materials obtained by sintering process for its characteristics from mechanical to electric or optical is well known fact. The role of liquid sintering phase has special importance in forming such contacts is empha-sized. It is helpful to introduce a 3D object formed by a fractal body moving around the ceramics grain, forming fractal Minkowski hull (FMH). Here, some properties of FMH are studied and some applications are suggested. This leads to a natural generalization of the classic hull, introducing fractal forms, which, helps in realistic description of the grains surface. This concept is useful in defining the measure of closeness between two or more grains from disjoint FMH’s. In combination with space configuration of grains’ network such closeness measure introduce fractal configuration and measure of intergranular contacts of different thickness. It causes many versa-tile microelectronic situations that implies corresponding material behavior. Using FMH, the extreme situations: contact – no contact are refined to several sub-situations that then explain some details connected to micro-capacities, thermodynamics, ferroelectric etc. in terms of fractal dimension of the hull.

BASIC SCIENCE DIV S4: Fundamentals of Mechanical Response

Mechanical BehaviorRoom: Nautilus CSession Chairs: Ivar Reimanis, Colorado School of Mines; Gerhard Dehm, Max-Planck-Institute for Eisenforschung GmbH

2:00 PM(EAM-BASIC-S4-001-2018) Chemo-Mechanical Failure Mechanisms in Ceramic Nanocomposites (Invited)B. W. Sheldon*1

1. Brown University, School of Engineering, USA

The volume changes that are associated with composition variations in a solid can induce significant stresses, when these expansions or contractions are physically constrained. These phenomena are important in a variety of energy-related materials, where they lead to complex interactions between electrochemical and mechanical driving forces. We have employed in situ measurements of these stresses along with a variety of other in situ and ex situ characteriza-tion methods, to obtain critical information about how the relevant mechanisms operate in different types of materials. One important example is ceramic electrolytes which are currently receiving wide-spread attention for applications in solid state batteries. The high elastic modulus and relatively low fracture toughness of these mate-rials can be problematic. In considering different approaches for


Abstracts

creating damage tolerant structures, it is important to recognize that the toughening mechanisms in these materials can be limited by the relatively small dimensions that are relevant in typical batteries. Thus nanoscale reinforcements are a logical option for improving fracture resistance. Recent experiments and analyses which explore relevant failure mechanisms and fracture toughness in these and other nanostructured ceramics will be presented.

2:30 PM(EAM-BASIC-S4-002-2018) Ferroelastic switching as a route to enhanced toughness: Understanding the role of coercive stress (Invited)C. S. Smith1; J. A. Krogstad*1

1. University of Illinois at Urbana-Champaign, Materials Science and Engineering, USA

In the earliest descriptions of ferroelastic toughening, terms such as the transformation strain, coercive stress and process zone param-eters were included following other crack tip shielding models. In the years that have followed, constitutive models have become more sophisticated, incorporating crystal orientation, rate behaviors, and several other factors. However, further development of these models has been limited by the paucity of experimental observations linking ferroelastic switching with critical, yet common, microstructural variations (i.e. grain size, nearest neighbor orientations, secondary/grain boundary phases, etc.). Here, we will present a systematic experimental approach to activating ferroelastic switching in specific microstructural configurations, wherein each grain contains a single domain. Exploration of single domain grains via in situ microscopy techniques further enables study of ferroelastic domain nucleation, which is anticipated to be a much more efficient toughening route, but also more likely to be preempted by fracture. Distinguishing between domain nucleation events and domain motion events will shed light on the use and interpretation of coercive stress in the context of ferroelastic toughening.

3:00 PM(EAM-BASIC-S4-003-2018) Combining high strength and moderate ductility in a novel ceramic coating: A combined ab initio and micromechanical study on Mo2BCR. Soler*1; S. Gleich1; H. Bolvardi2; C. Kirchlechner1; J. M. Schneider2; C. Scheu1; G. Dehm1

1. Max-Planck-Institute for Eisenforschung GmbH, Germany2. RWTH Aachen University, Germany

Combining high hardness, extreme stiffness, and moderate tough-ness are vital when developing new advanced ceramic coatings. Within this study, we propose a novel design strategy to develop new material systems that combine these traditionally self-excluding mechanical properties. The strategy comprises: (i) ab initio calcula-tions, used to conceive new systems with tuned chemical structures. Here, focus is laid on the valence electron concentration (VEC) as a predictor of the fracture toughness. (ii) Combined physical vapor deposition processes and advanced characterization techniques, used to synthesize and characterize the ab initio designed phases. And (iii) state-of-the-art nanomechanics, used to probe the mechan-ical properties of these microscale material systems. Within this talk, a study preformed on X2BC (X=Ti, V, Zr, Nb, Mo, Hf, Ta, W) phases will be shown. Emphasis will be laid on the Mo2BC system, revealed as a very hard (∼25 GPa), very stiff (∼350 GPa), and moderately ductile (∼4 MPa√m) material. Mo2BC films deposited at various temperatures will be analyzed with respect to their degree of crys-tallinity, grain size, and chemical homogeneity to elucidate how the microstructure influences the mechanical properties. Finally, some conclusions on the validity of the VEC as a predictor of the fracture toughness in X2BC phases will be drawn.

3:15 PM(EAM-BASIC-S4-004-2018) Organically linked iron oxide nanoparticle supercrystals with exceptional isotropic mechanical propertiesG. A. Schneider*1; B. Domenech1; D. Giuntini1; B. Bor1; D. Benke1

1. Hamburg University of Technology, Germany

It is commonly accepted that the combination of the anisotropic shape and nanoscale dimensions of the mineral constituents of natural biological composites underlies their superior mechanical properties when compared to those of their rather weak mineral and organic constituents. Here, we show that the self-assembly of almost monodisperse iron oxide nanoparticles in supercrystals linked together by a thermally induced crosslinking reaction of oleic acid molecules leads to a nanocomposite with exceptional bending modulus of 114 GPa, nanohardness of up to 4 GPa and microbeam strength of up to 630MPa. By using a nanomechanical model, we determined that these exceptional mechanical properties are domi-nated by the covalent backbone of the linked organic molecules. Because oleic acid has been broadly used as nanoparticle ligand, our crosslinking approach should be applicable to a large variety of nanoparticle systems.

3:30 PM(EAM-BASIC-S4-005-2018) Bond length, elastic and thermal properties as a function of crystallite-size in unary nano-oxidesS. Chan*1

1. Columbia University, Applied Physics, USA

Lattice-parameter of nano-oxides expands 0.1 to 0.5% as size decreases to ~5nm from micron-size for five oxides suggesting a negative surface stress in each case. The five unary oxides are CeO2, MgO, Cu2O, Fe3O4, and Co3O4. This is different from the posi-tive surface stress observed earlier in nanoparticles of noble metals. Surface stress can be calculated from the measured lattice-expan-sion as oxide crystallite-size decreases. This investigation is possible because of the mono-dispersed nature of the nano-oxide in each size-batch. We have also studied the pressure and thermal response of the lattice-parameter of nano-ceria and nano-MgO as a function of crystallite-size. Hence, bulk modulus (B) and coefficient of lattice thermal expansion (CLTE or alpha) were measured a function of crystallite-size. Bulk modulus peaks around 33nm for nano-ceria and 14nm for nano-MgO. In both cases there is a quick decline as size further decreases. The coefficients of lattice thermal expan-sion in both cases decrease rapidly after 15nm to ~60% of the bulk values. The findings have a number of implications for the bonding, surface-stress and elastic energy stored in thee nanoparticles.


Modeling and CharacterizationRoom: Nautilus BSession Chair: Dan Lewis, Rensselaer Polytechnic Institute

2:00 PM(EAM-BASIC-S5-008-2018) Microstructure and Kinetics Associated with First-Order Phase Transformations (Invited)J. Rickman*1

1. Lehigh University, Materials Science and Engineering, USA

We describe the evolution of spatio-temporal correlations associated with a first-order phase transformation. In particular, we examine the impact of spatial correlations on the correlation functions that characterize the transformation and outline the quantification of the resulting microstructures. Computer simulation is used to examine


Abstracts

a variety of nucleation and growth scenarios, both in bulk and thin films, and various metrics are proposed to characterize associated microstructures. Finally, we show that, in many instances, one can understand nucleation and growth processes in terms of simple stochastic geometric models.

2:30 PM(EAM-BASIC-S5-009-2018) In-situ SEM study of crystal faceting and surfaces during selective reduction of metals from oxides (Invited)S. T. Misture*1

1. Alfred University, MSE, USA

Selective reduction of metallic nanoparticles from oxides is an important process for catalyst preparation. We demonstrate the use of in-situ SEM and diffraction for the study of particle morpholo-gies and catalyst microstructures during reduction and reoxidation reactions. Maturation of the catalyst microstructure via redox reac-tions dramatically improves performance in some cases, and in-situ FESEM provides the first hints at the key microstructural features leading to performance enhancements. Beginning with highly faceted oxides, the reduction reaction creates crystallographical-ly-oriented surface cracking and yields complex surfaces decorated by metal nanoparticles. While quantification of the microstruc-tures is not yet feasible, the study demonstrates that, for example, activation of CO2 on surface features directly scales to sulfur toler-ance during reforming reactions. Insights into beam damage when imaging at high temperature are also included.

3:00 PM(EAM-BASIC-S5-010-2018) Surface Faceting Behavior in NiO-MgOD. Lowing*1; C. Handwerker1; J. Blendell1

1. Purdue University, USA

NiO-MgO in an isomorphous alloy system with Wulff shapes that change from predominantly (100) and rough regions for MgO to (100) and (111) for NiO measured using shape transitions of alloy powders annealed in air at 1500C. In this study, the temperature dependence of faceting transitions in MgO-NiO were measured using a combination of AFM and EBSD on polished, then annealed, polycrystals, thus providing a range of surface normals and orien-tation constraints. The population of facet orientations, the extent of rough regions in the Wulff shape, and the size and stability of the dominant facets were measured along with the effect of grain boundary grooving on facet formation as a function of composition and temperature. Individual grain surfaces were tracked over time to characterize facet nucleation and growth/coarsening. Models for how fully faceted grain surfaces might evolve will be presented and specific challenges with respect to fabricating dense samples in MgO-NiO system will be discussed.

3:15 PM(EAM-BASIC-S5-011-2018) Novel Processing Routes to Bulk Nanostructured Ceramics (Invited)E. Gorzkowski*1

1. Naval Research Lab, USA

At the US Naval Research Lab we have been utilizing and devel-oping several new processing routes to tailor unique microstructures (fully dense bulk nanostructured) in metals and ceramics. These techniques include 2 stage sintering, aerosol deposition, high-pres-sure processing, microwave sintering, and electrically assisted sintering. The impetus is the many theoretical and experimental studies showing tremendous enhancements in functional prop-erties of nanostructured materials including magnetic exchange coupling, thermoelectric energy conversion, and mechanical response. However, these improvements are generally only expected when porosity is negligible and the microstructural length scales

are well below 50nm, which is a technological challenge. One tech-nique that will be highlighted is the NRL developed Enhanced High Pressure Sintering (EHPS) approach. EHPS incorporates strin-gent environmental control and utilizes high pressures to exploit the increased pristine surface potential of nanoparticles for surface -energy-driven densification. Importantly, fully dense nanostruc-tures can be synthesized with negligible change to the pre-sintered crystallite length scales. Using this approach, fully-dense nano-crystalline ceramics with grain sizes <10nm have been synthesized allowing rigorous evaluation of standing theories in the mechanical behavior of ceramics, including Hall Petch break down and indenta-tion size effects.

3:45 PM(EAM-BASIC-S5-012-2018) Innovative Processing and Scalable Consolidation of Metal-Ceramic NanocompositesK. Anderson*1; R. P. Vinci1; H. M. Chan1

1. Lehigh University, USA

Nanoscale metal-ceramic composites offer unique and exciting properties, but are limited by complex processing requirements. Exploiting phase transformations such as eutectoid decomposition and partial reduction of mixed oxides presents a straightforward means of producing composites with tunable microstructures. These reactions were employed using powder compositions in the Co-Ti-O and Cu-Al-O systems. CoTiO3-TiO2 composites were generated through a eutectoid transformation from the CoTi2O5 phase. Subsequently applying partial reduction to this composite produces a Co-TiO2 composite with a novel microstructure. Cu-Al2O3 composites were created through the partial reduction of the CuAlO2 phase. By varying time and temperature both the eutectoid and partial reduction reactions can be controlled to yield composite microstructures of tunable scale, including nanocompos-ites. By using powders, bulk composite specimens can be produced through a scalable process utilizing SPS to minimize coarsening. The effect of processing variables on the resulting microstructures will be discussed in reference to the morphology and scale of the composites, as well as the crystallographic relationships between the phases. Microstructures were characterized through XRD, SEM, EBSD, and TEM.

4:00 PM(EAM-BASIC-S5-013-2018) Modeling Domain and Topological Defect Structure Evolution in Hexagonal Manganite Using Phase-field Simulations (Invited)F. Xue1; X. Wang2; S. Cheong3; L. Chen*1

1. The Pennsylvania State University, Materials Science and Engineering, USA

2. Beijing University of Technology, China3. Rutgers University, USA

Hexagonal manganite h-REMnO3 (RE, rare earths) is one important type of multiferroic improper ferroelectrics displaying intriguing domain and topological defect evolution. The six domain variants in h-REMnO3 form vortex and antivortex cores, or generally called “topological defects”. We obtain the temporal and spatial evolu-tion of the vortex domain structures using phase-field simulations and explore the mesoscale mechanisms for the vortex-antivortex annihilation, evolution of vortex loops, and domain wall motion with and without external electric fields. It is demonstrated that the vortex motion and vortex-antivortex annihilation control the kinetics of domain structure evolution. It is discovered that the vortex loops may undergo three types of topological transfor-mations, i.e., shrinking, coalescence, and splitting in analogy to dislocations. Furthermore, it is shown that an in-plane strain can unfold the vortices into single-chirality striped domains. The depen-dences of the stabilities of the vortex domains and striped domains on temperature and strain will be discussed.


Abstracts


Electronics Materials for 5G Telecommunications Applications IIRoom: Magnolia A/BSession Chairs: Nate Orloff, NIST; Thomas Wallis, National Institute of Standards and Technology

2:00 PM(EAM-ELEC-S6-007-2018) Microwave Characterization of Nanomaterials for 5G Applications (Invited)T. M. Wallis*1; S. Berweger1; P. Kabos1

1. National Institute of Standards and Technology, Applied Physics Division, USA

Radio frequency (RF) nanoelectronics focuses on the study and engineering of RF and microwave devices that are enabled by nanotechnology. The application of RF nanoelectronic devices to advanced applications such as 5G communications will only be realized with accurate measurements of nanomaterials. Early measurement approaches extended on-wafer, measurement tech-niques to devices that incorporate nanoscale building blocks, including nanowires and nanotubes. In general, these techniques require calibration procedures that enable the scattering param-eters of the device or material under test to be de-embedded from the effects of the test equipment. Beyond overall device character-ization, there is an additional need for microwave measurements that are spatially localized, providing insight into the impacts of intra-device defects, interfaces, and other localized material proper-ties. An effective method is to combine the nanometer-scale spatial resolution of scanning probe microscopy with broadband sensitivity in the frequency range from 100 MHz to 40 GHz, thus producing a “near-field scanning microwave microscope” (NSMM). A further objective is to use modeling and simulation to extract intrinsic prop-erties of nanomaterials from both scattering parameter and NSMM measurements.

2:30 PM(EAM-ELEC-S6-008-2018) Defect Mitigating (SrTiO3)n(BaTiO3)mSrO Superlattices for mmWave Tunable Dielectrics (Invited)N. Dawley*1; X. Lu2; A. Hagerstrom2; G. Olsen3; M. Holtz3; C. Lee1; J. Zhang1; C. Fennie3; D. Muller3; N. Orloff2; J. Booth2; D. Schlom1

1. Cornell University, Materials Science and Engineering, USA2. NIST, USA3. Cornell University, Applied and Engineering Physics, USA

The Ruddlesden-Popper (RP) superlattice series, (ABO3)nAO, has been identified as a defect mitigating structure via a proposed mechanism in which the (AO)2 layer accommodates the local non-stoichiometry of the crystal by changing its area. In the strained (SrTiO3)nSrO thin film phase we have demonstrated record tunable dielectric performance at gigahertz (mmWave) frequencies, a region where point defects significantly contribute to dielectric loss. In contrast, the parent phase commonly used for frequency tunable microwave circuit elements, BaxSr1-xTiO3, experiences large attenu-ation at gigahertz frequencies arising from dielectric loss related to point defects. In this work we use molecular-beam epitaxy (MBE) to grow related RP phases containing BaxSr1-xTiO3, specifically (SrTiO3)n(BaTiO3)mSrO. The first five members of this RP homolo-gous series (n = 1- 5) have been grown on DyScO3 (110) using MBE and characterized by x-ray diffraction. We use density functional theory (DFT) to predict and understand the ferroelectric proper-ties of these films. In-plane measurements of the dielectric constant have been made as a function of temperature and frequency in the

gigahertz frequency regime. We use scanning transmission electron microscopy (STEM) and electron energy loss spectroscopy (EELS) to identify barium and (SrO)2 fault placement, and find high quality films.

3:00 PM(EAM-ELEC-S6-009-2018) Broadband nonlinear dielectric spectroscopy of materials with polar nano-regions (Invited)A. Hagerstrom*1; E. Marksz2; C. Long1; N. Orloff1

1. National Institute of Standards and Technology, Communications Technology Laboratory, USA

2. University of Maryland, Materials Science And Engineering, USA

Ferroelectric materials are often characterized by the dependence of their permittivity (also called dielectric constant) on a static elec-tric field. However, in many applications of interest, a circuit must be dynamically reconfigured to adapt to a changing environment. In these cases, a circuit’s tuning speed is an important figure of merit. This figure of merit is ultimately determined by the mate-rial’s dynamics under a time-varying applied electric field. More specifically, tuning speed is determined by the nonlinear permittivity – a quantity that is fundamentally inaccessible to linear measurements like impedance spectroscopy, and cannot be inferred from a material’s tuning under a static field. In materials with polar nano-regions, the nonlinear permittivity is expected to have non-trivial frequency dependence from millihertz to terahertz. To capture this frequency dependence in a model, we require broadband measurements. Here we report measurements of the 2nd order nonlinear permittivity of a 1 micron thick Ba0.5Sr0.5TiO3 film grown on a LaAlO3 substrate by pulsed laser deposition. We characterized nonlinear permittivity from DC up to 25 GHz, and provide a phenomenological model based on Landau-Ginsburg-Devonshire theory.

4:00 PM(EAM-ELEC-S6-010-2018) Enhanced Quality Factor of Mg2TiO4-based Ceramics at Microwave FrequenciesE. Kim*1

1. Kyonggi University, Department of Materials Engineering, Republic of Korea

Microwave dielectric ceramics with low loss are of increasing interest for 5G wireless communication systems, such as global communication satellites, mobile communications, and radar detec-tors. For the effective search and develop the microwave dielectric ceramics with high quality factor, the relationships between micro-wave dielectric properties of Mg2TiO4-based ceramics with inverse spinel structure and the structural characteristics were investi-gated. By substitution of tetravalent cation, the characteristics of the bond between the cations and oxygen ions in oxygen octahedra can be modified to affect the dielectric properties of Mg2TiO4-based ceramics. Typically, two types of cation substitutions will be discussed; Mg2Ti1-x(Mg1/3B2/3)O4 (B=Nb5+,Ta5+,Sb5+) (0.025≤x≤0.15), and Mg2Ti0.95(MgxNb0.8-0.4x)0.05O4 (0.0≤x≤1.0). Quality factor (Qf) of the specimens was dependent on the bond valence of Ti-site and packing fraction of Mg2TiO4-based ceramics. The dielectric constant (K) and temperature coefficient of resonant frequency (TCF) of the specimens will also be discussed based on the structural characteris-tics of inverse spinel structure.

4:15 PM(EAM-ELEC-S6-011-2018) Continuously tunable acoustic-wave-resonator-based RF filters for next generation wireless communication transceivers (Invited)D. Psychogiou*1

1. University of Colorado, Boulder, Electrical Computed and Energy Engineering, USA

Emerging wireless communication systems are increasingly calling for RF front-ends with multi-functional and multi-standard


Abstracts

operability which in turn create the need for RF filters with small physical size, low loss and adaptive transfer function. Whereas acoustic-wave RF filters such as the ones using SAW or BAW reso-nators have been identified as the key filtering technology for 4G/5G RF front-ends, their operation is limited by narrow fractional band-width (FBW, << electromechanical coefficient kt

2) and the lack of transfer function adaptivity. In response to the aforementioned limitations, we have developed a new class of miniaturized RF filters in which acoustic-wave resonators are effectively combined with electromagnetic elements. The proposed RF design methodology is based on hybrid acoustic-wave lumped-element resonator (AWLR) arrays that facilitate the realization of a diverse number of transfer functions which are of critical importance to modern RF front-ends. These include quasi-elliptic bandpass filters, reflective- and absorp-tive- type bandstop filters as well as filters with multi-band response. More importantly, the proposed AWLR RF design approach allows for the first time the realization of acoustic-wave filters with contin-uously tunable transfer function and fractional bandwidth >kt

2.

4:45 PM(EAM-ELEC-S6-012-2018) Tunable Photoconductive Resistor for Multi-State Calibrations and Materials CharacterizationJ. Drisko*1; X. Ma2; J. Davila-Rodriguez1; J. Booth1; A. Feldman1; F. Quinlan1; N. Orloff1; C. Long1

1. National Institute of Standards and Technology, USA2. Lehigh University, USA

Millimeter-wave materials characterization is an essential tool in the development of 5G technologies, high-frequency electronics, next generation computing, fundamental materials science, and more. Unfortunately, raw millimeter-wave measurements are typically dominated by systematic errors introduced by cables, connectors, adaptors, and probes. To correct these systematic errors, one must measure a set of reference standards with known electrical prop-erties. These measurements are time consuming and introduce uncertainty due to the variability in connections. Here, we present a silicon photoconductive device that can be placed into multiple known electrical states by applying varying intensities of laser light. We show that this multi-state device can replace a full set of calibra-tion artifacts, potentially making the error correction process much simpler and faster. This demonstration opens the door to new types of multi-state devices based on other materials systems with tunable electrical properties while also offering new possibilities such as the creation of self-calibrating devices.

5:00 PM(EAM-ELEC-S6-013-2018) Nondestructive Electrical Property Measurements by Mutlireflect Thru to 110GHzN. B. Popovic*2; J. Drisko2; S. E. Shaheen1; E. Garbozi2; C. Long2; N. Orloff2

1. University of Colorado, Boulder, Electrical Engineering, USA2. National Institute of Standards and Technology, USA

As 5G communication systems are being developed, understanding the electrical properties of prospective materials quickly and accu-rately is important. While there are many ways to measure electrical properties of materials, broadband techniques are particularly useful. One way to measure broadband electrical properties is to fabricate electrical devices directly onto the material-of-interest. This is time-consuming, expensive, and destructive. Alternatively, a nondestructive method to measure electrical properties places the material-of-interest onto an electrical measurement device, often referred to as flip-chip. The most accurate broadband elec-trical measurement technique uses multiple coplanar waveguide transmission lines that have different lengths, called multiline thru-reflect-line. However, combining flip-chip and multiline TRL requires machining the material into a specific geometry, which is destructive. Here, we combined flip-chip with a multireflect thru

(MrT) technique to achieve the broadband accuracy of multiline TRL without destroying the sample. Instead of multiple coplanar waveguide transmission lines, our technique uses multiple coplanar waveguide short and open reflects that have different offset lengths, and a 10x10mm square of material. This advancement in material measurement will provide quicker, more accurate electrical proper-ties for a broader range of materials.


Thin Film Growth: A STEM StudyRoom: Orange DSession Chair: Hyoungjeen Jeen, Pusan National University

2:00 PM(EAM-ELEC-S8-001-2018) Native formation of oxide/oxide and oxide/nitride nano-composites (Invited)J. LeBeau*1; J. Dycus1; W. Xu1; P. Bowes1; K. Mirrielees1; E. D. Grimley1; D. Irving1

1. North Carolina State University, Materials Science & Engineering, USA

In this talk, I will show how certain material surfaces can serve as the template for native two-dimensional multilayer nano-composites. When pristine material surfaces are exposed to air, highly reactive broken bonds can promote the formation of surface oxides with structures and properties that differ from bulk. Determination of the oxide structure, however, is often elusive through the use of indirect diffraction methods or techniques that probe only the outer most layer. Using aberration corrected scanning transmission electron microscopy, I will show how we can directly reveal, and as a function of depth, the structure of native two--dimensional oxide compos-ites that form on Al/GaN and SrTiO3 surfaces. In the case of the nitrides, I’ll demonstrate that the oxide layers are composed of tetra-hedra--octahedra cation--oxygen units, similar to bulk β-Ga2O3. I will also highlight our recent work on imaging (110) SrTiO3 surfaces via in-situ STEM at temperatures up to 900C where peri-odic surface defects, similar to dislocations, are found. Through STEM imaging, electron energy loss spectroscopy, and density func-tional theory, I will discuss the combined role of lattice misfit and charge compensation dictating the observed nano-composite surface structure.

2:30 PM(EAM-ELEC-S8-002-2018) Atomic-Scale Analysis of Phases of Layered In2Se3 for high performance photodetectors (Invited)Z. Wang*1

1. International Iberian Nanotechnology Laboratory (INL), Department of Quantum Materials, Science and Technology, Portugal

III-VI semiconductors are currently being investigated as potential candidates for optoelectronic and phase change memory devices. Among several III-VI semiconductors, In2Se3 is an interesting mate-rial due to its multiple phases and excellent optical properties. In2Se3 is a direct bandgap material with a layered structure. There are at least five different phases of In2Se3 (α, β, γ, δ, and κ). The α and β -phases can crystallize in both α(3R) and α(2H) crystal structures while γ -phase has a defective wurtzite structure. The κ–phase is reported to have a structure more similar to the α-phase with larger unit cell. For device applications, it is important to have single phase materials because different phases of In2Se3 can co-exist. Here, we investigate how growth temperature, fluxes and type of substrates influence the growth of In2Se3 using molecular beam epitaxy. We have found that Se-rich and high temperatures favour growth of β phase In2Se3 while γ phase is obtained in In-rich conditions and low temperatures on GaAs (100) substrates. Within the same parameter


Abstracts

range, γ phase was predominant on GaAs (111) A substrates. The phases of In2Se3 on mica substrates can also be controlled by tuning the growth conditions. We also combine scanning transmission electron microscopy with density functional theory calculations to investigate atomic structure of the grown In2Se3 and the defects.

3:00 PM(EAM-ELEC-S8-003-2018) Metrology of polar displacements across interfaces and domain walls in complex oxides: A high resolution aberration-corrected electron microscopy study (Invited)N. Alem*1


Structural distortions at domain walls and interfaces in complex oxides can directly tune the resulting macroscale physical and electronic properties leading to ferroelectricity, multiferroics, photo-voltaic behavior, and two dimensional electron gas. While domain walls and interfaces have been a well-studied subject for decades, little is known about their local atomic and chemical structure, and the metrology of their polar displacements. The past decade has seen incredible progress in the ability to image the atomic and chemical structure of nanostructures with the development of aberration-cor-rected transmission electron microscopy. Using high resolution aberration-corrected scanning/transmission electron microscopy (S/TEM) imaging, this presentation will focus on our recent efforts on quantitatively probing the metrology of the polar displacements in a variety of complex oxide nanostructures including transition metal oxide brownmillerites and Congruent LiNbO3. STEM imaging is used to probe and quantify the sub-Angstrom structural distortions and polarization effects across the interfaces in epitaxial (SrFeO2.5)1/(CaFeO2.5)1 superlattices and 180° domain walls in congruent LiNbO3.

Thin Film Growth and FunctionalitiesRoom: Orange DSession Chair: Julia Mundy, Harvard University

4:00 PM(EAM-ELEC-S8-004-2018) Magnetic and structural order and deviations from rule of mixtures in entropy stabilized oxide heterostructuresP. B. Meisenheimer*1; T. Kratofil1; J. Heron1

1. University of Michigan, Materials Science and Engineering, USA

Entropy-stabilized materials are stabilized by the configurational entropy of the constituents, rather than the enthalpy of formation of the compound. A unique benefit to entropic stabilization is the increased solubility of elements, which opens a broad composi-tional space with subsequent local chemical and structural disorder resulting from different atomic sizes and preferred coordinations of the constituents. As the magnetic and electronic properties of oxides are strongly correlated to their chemistry and electronic structure, entropy stabilization could lead to interesting and novel proper-ties. Anisotropic magnetic exchange and the presence of a critical blocking temperature indicates that the entropy-stabilized oxides considered here are antiferromagnetic. Changing the composi-tion of the oxide tunes the disorder and exchange bias and here we exploit this tunability to enhance the strength of the exchange field by a factor of 10x at low temperatures, when compared to a CoO heterostructure. Significant deviations from the rule of mixtures are observed in the structural and magnetic parameters, indicating that the crystal is dominated by configurational entropy. Our results reveal that the unique characteristics of entropy stabilized materials can be utilized to engineer magnetic functional phenomena in oxide thin films.

4:15 PM(EAM-ELEC-S8-005-2018) Synthesis of Ruddlesden-Popper strontium iridate epitaxial thin films by kinetic controlX. Liu*1; Y. Cao1; B. Pal1; S. Middey4; M. Kareev1; Y. Choi3; P. Shafer2; D. Haskel3; E. Arenholz2; J. Chakhalian1

1. Rutgers University, Physics & Astronomy, USA2. Lawrence Berkeley National Laboratory, USA3. Argonne National Laboratory, USA4. Indian Institute of Science, India

We report on the selective fabrication of high-quality Sr2IrO4 and SrIrO3 epitaxial thin films from a single polycrystalline Sr2IrO4 target by pulsed laser laser. We discover that within a relatively narrow range of substrate temperature, the oxygen partial pressure plays a critical role in the cation stoichiometric ratio of the films, and trig-gers the stabilization of different Ruddlesden-Popper (RP) phases. Resonant X-ray absorption spectroscopy measurements taken at Ir L-edge and O K-edge confirm the formation of proper chemical composition for each RP phase, demonstrate the presence of strong spin-orbit coupling, and reveal the electronic and orbital structures of both compounds. These results suggest that in addition to the conventional thermodynamics consideration, higher members of the Srn+1IrnO3n+1 series can be achieved by kinetic control away from the thermodynamic limit. These findings offer a new approach to fabricating ultra-thin films of the RP series of iridates.

4:30 PM(EAM-ELEC-S8-006-2018) On the epitaxial relationships between CdO thin films and sapphire substratesE. D. Grimley*1; K. Kelley1; E. Sachet1; J. Maria1; J. LeBeau1

1. North Carolina State University, Materials Science and Engineering, USA

CdO thin films have recently garnered increased attention because of the ability to tune their mid infrared optical properties by extrinsic doping. As such, CdO is finding increased use in plasmonic devices and other applications. These materials have typically been grown on MgO substrates which share its rock salt structure. These films have also been shown to grow on c- and r-plane sapphire substrates, and they yield optical properties similar to those grown on MgO. In this presentation, we investigate the origin of this epitaxial relation-ship that exists between CdO and sapphire as revealed by scanning transmission electron microscopy. Our results reveal that the rock salt structure integrates onto c-plane sapphire via a high-order CdO plane and a highly ordered interface structure. This is in contrast to the epitaxy of CdO on MgO, which forms a high density of misfit dislocations and forms large lattice strains that persist several nano-meters into the film and substrate. We discuss the structure of these interfaces, the formation of boundaries between different rotational variants due to substrate steps on sapphire, and the persistence of the structure to large film thicknesses. These results highlight how high-quality interfaces can occur in unexpected instances.

4:45 PM(EAM-ELEC-S8-007-2018) Time-dependent thermoreflectivity of doped CdO thin films with mid-IR surface plasmon polaritonsE. Radue*2; E. Runnerstrom1; J. Maria1; P. E. Hopkins2

1. North Carolina State University, Materials Science and Engineering, USA2. University of Virginia, Mechanical and Aerospace Engineering, USA

Doped CdO has been shown to be a tunable low loss plasmonic host in the mid-IR range, unlike most materials that support plasmonic resonances. In order to incorporate these films into novel plas-monic technologies, we need to have an accurate measurement of how heat diffuses through the films and interfaces. Our study looks at the thermal conductivity of CdO thin films doped with Yttrium at different concentrations, and examines how surface plasmon polaritons effect the thermal conductivity of the CdO films, using


Abstracts

time dependent thermoreflectance (TDTR). TDTR is a pump-probe measurement, where a high rep pulsed laser beam heats layers of thin films, while a probe pulse scans over time to track the temperature dependent change in reflectivity. Our preliminary results show that layers of Y doped CdO with different charge concentrations show no thermal resistance from the interface between the CdO layers despite the electronic barriers at the interface, and that the thermal conduc-tivity of the stacks combined is equal to a CdO film with the average carrier concentrations of the stacks. We will also be measuring the thermal conductivity of doped CdO with surface plasmon polaritons turned on and off, to examine if there is a plasmonic contribution to the thermal conductivity.

5:00 PM(EAM-ELEC-S8-008-2018) Interface-Thickness Optimization of Lead-Free Oxide Multilayer Capacitors for High-Performance Energy Storage (Invited)M. Liu*1; Z. Sun1; L. Wang2; Z. Liang2; Q. Fan2; L. Lu2; C. Ma3; X. Lou2; H. Wang2; C. Jia2

1. Xi’an Jiaotong University, School of Microelectronics, China2. Xi’an Jiaotong University, China3. Xi’an Jiaotong University, Material Science and Engineering, China

The effects of interface density and total multilayer film thickness on the dielectric properties and breakdown behaviors have been revealed in this work by investigating the environment-friendly energy storage multilayer films of Ba0.7Ca0.3TiO3 and BaZr0.2Ti0.8O3 dielectrics. Numerical simulations based on finite element method have given the breakdown process vividly, which is agreed well with the experimental results. Moreover, not only the ultrahigh energy storage density of 51.8 J/cm3 with great efficiency of 81.2% at room temperature but also robust thermal stability has been obtained by optimizing the interface density and total thickness. High energy density above 25.1 J/cm3 and excellent efficiency over 63.6% from room temperature to 200 oC provide the solid basis for potential applications of the multilayer systems in hash environment.


Substitition and Sustainability in Functional Materials IRoom: Citrus BSession Chair: Derek Sinclair, University of Sheffield

2:00 PM(EAM-ELEC-S9-001-2018) Low-temperature bio-inspired synthesis of functional oxides (Invited)R. Boston*1; I. M. Reaney1; D. C. Sinclair1

1. University of Sheffield, Materials Science & Engineering, United Kingdom

Traditionally, oxide-based electroceramics have been made via solid-state synthesis, which whilst reliable, suffers from several inherent drawbacks. Solid-state syntheses can be extremely slow, requiring many heating and processing steps to produce a phase pure final product. It also gives no control of size or morphology, a major disadvantage when nanoscale materials are required or beneficial, and products can suffer from poor homogeneity, particularly in cases where there are a large number of constituent oxides. Recently, biotemplate- and solvent-mediated syntheses have been gaining popularity as a low-temperature way to create homogenously

mixed functional oxides. The techniques give exquisite control over nanomorphology, and generally only require low temperatures to promote phase formation. The polydentate chelating ability of many naturally occurring polymeric molecules make them highly effective at uptaking metal ions from solution, keeping them spatially sepa-rated during heating, circumventing many of the issues associated with traditional processing routes. I will present the underpinning concepts of bio- and solvent- templating, and give examples of the accessible structures and materials, including recent work on dielec-tric and thermoelectric materials, and on the growth of nanowires in a variety of functional oxides.

2:30 PM(EAM-ELEC-S9-003-2018) Thermoelectric property optimization of reduced Sr1-3x/2RExTiO3-δ

W. L. Schmidt*1; G. D. Lewin1; A. Iyasara1; D. C. Sinclair1; I. M. Reaney1


Thermoelectric generators (TEGs) are currently used in niche appli-cations and are based on intermetallic materials with expensive and toxic constituents such as lead, tellurium, antimony, germanium and silver. Many oxide ceramics exhibit promising thermoelectric prop-erties and are composed of less toxic raw materials. In this study, the thermoelectric figure of merit, ZT = S2σ/κ, for n-type perovskite oxides has been optimized in strontium titanate using an A-site vacancy doping mechanism, Sr1-3x/2RExTiO3-δ (RE = Rare Earth). To achieve a high electrical conductivity (σ) and in doing so opti-mise ZT, materials were prepared under reducing conditions. Variable processing treatment of the powders affected σ but showed limited effect on the Seebeck coefficient (S) or thermal conductivity (κ). While this approach has led to high ZT materials (0.41), further optimization of oxides is required before they can achieve commer-cial usage within TEGs.

2:45 PM(EAM-ELEC-S9-004-2018) Materials and manufacturing supply chain life cycle sustainability: The next frontier (Invited)L. Koh*1

1. The University of Sheffield, Advanced Resource Efficiency Centre, United Kingdom

Life Cycle Assessment (LCA) provides a robust structure for the assessment of the environmental impacts of material, product or service. It is a well established approach that dates back to the 60s. Generally, there are two main modelling methods, namely process LCA and input-output LCA. While each methodology alone has limitations, a hybrid LCA allows for capturing the broader system boundary and assessing the direct and hidden environmental impact across the supply chain. The Supply Chain Environmental Analysis Tool (SCEnAT) successfully integrates the process LCA and envi-ronmental Input-Output LCA through supply chain mapping, carbon calculations, low carbon interventions, supply chain perfor-mance evaluation and informed decision making. By working with different companies, the tool is able to provide informed decisions to enable managers to make both carbon and efficiency savings in the supply chain. Moving forward, supply chain LCA must be successfully integrated into initiatives such as ‘Factory of the Future’, ‘Industrie 4.0’ and ‘Made in China 2025’. This will be achieved by working closely with industry, policy governance and academia to ensure that any advances are made with full understanding of their effect on sustainability.


Abstracts

3:45 PM(EAM-ELEC-S9-005-2018) Grain Boundary Engineering Opportunities for Novel Composites with the Aid of Cold Sintering (Invited)C. Randall*2; J. Guo3; Z. Xuetong3; T. Herisson de Beauvoir1

1. MRI - Pennsylvania State University, USA2. Pennsylvania State University, Materials Science and Engineering, USA3. Pennsylvania State University, USA

As we have already suggested, cold sintering enables incompat-ible materials to be co-processed. These can be materials that can then be integrated into layers or as nano-intergranular phases between a major ceramic phase. These minor phases can control the properties of transport across grain boundaries and enable new functionality to be realized. In this talk, we will consider the incor-poration of small volume fractions of polymer into nanometer scale grain boundaries that can impact conditions, mechanical prop-erties, and thermal properties. One example to be shown will be a ZnO-PTFE composite. We will also consider nanoparticles in the grain boundary regions to also lead to unique properties.

4:15 PM(EAM-ELEC-S9-006-2018) Development of Lead-free PTCR MaterialsD. U. Seifert*1; M. J. Hoffmann1; M. Hinterstein1

1. Karlsruhe Institute of Technology, Institute for Applied Materials, Germany

Positive Temperature Coefficient of Resistance (PTCR) materials are widely used in self-regulating heating components. All PTCR mate-rials currently used for technical devices are based on the ceramic barium titanate (BT). However, BT has a Curie temperature (Tc) of approx. 120°C, which is relatively low for this purpose. Therefore, lead titanate is generally added to raise Tc and to modify the working temperature of the heating elements. New laws (RoHS – Restriction of Hazardous Substances), restricting the use of lead, serve primarily to protect the environment, but they also encourage the develop-ment of lead alternatives. The goal of our project is to develop a lead-free, semi-conducting PTCR ceramic with increased Tc based on BT. To accomplish this goal, we doped BT to generate the needed semi-conducting properties and then added a specific amount of bismuth sodium titanate (BNT) to the BT starting material in order to raise Tc. Since the electromechanical material properties are influenced by phase composition, microstructure, stoichiometry, homogeneity, the amount and type of dopant as well as the amount of BNT, careful controlling of the processing parameters is crucial. Therefore, we varied these parameters to determine the effect on the final ceramic product and then characterized the properties of the different ceramic compositions. This contribution will give insight in the development of lead-free PTCR ceramics based on BT.

4:30 PM(EAM-ELEC-S9-007-2018) Material characteristics from Cold Sintering Process (CSP) compared to conventional sinteringR. Floyd*2; X. Kang1; J. Maria2

1. North Carolina State University, USA2. Pennsylvania State University, USA

Substantial densification can be promoted by mixing an oxide with a liquid phase – provided some finite solubility of the two – and uniaxially pressing and heating the die. We refer to this as the Cold Sintering Process (CSP) due to the relatively low temperature required for densification. CSP has been successfully applied to a variety of binary and ternary ceramic compounds, including ZnO, WO3, Li2MoO4, etc. These materials exhibit high relative densities, up to >99%, and uniform microstructures with sharp grain bound-aries. CSP promotes a new method for densification of ceramic materials far below conventional sintering temperatures, allowing for control of grain sizes as well as stoichiometry in volatile complex

oxides. In this presentation, we discuss the extent of how certain Cold Sintered materials compare to their conventionally sintered counterparts, from a comprehensive study of effects on density, microstructure, secondary phase formation, permittivity, mechan-ical properties, and calorimetry based on sintering temperature, pressure, liquid phase fraction, and process time using an improved constant-pressure uniaxial press. This work will create a foundation for future studies on how CSP can be applied to material systems that otherwise require extreme thermal budgets or concern for constituent volatility.

4:45 PM(EAM-ELEC-S9-008-2018) The Influence of Electrode Geometry on the Average and Local Electrical Responses of ElectroceramicsR. A. Veazey*1; J. S. Dean1; A. S. Gandy1; D. C. Sinclair1

1. University of Sheffield, Materials Science and Engineering, United Kingdom

Impedance Spectroscopy is a useful technique to characterise the electrical properties of a wide range of materials and devices. Macroscopic contacts, where full top and bottom surfaces of a sample (usually a ceramic) are electrodes, can be used to obtain average bulk (grain) and grain boundary properties. Micro-contacts on the other hand obtain local properties or more targeted measure-ments of a material, such as individual grain boundaries in a ceramic or on a thin film grown on a substrate. In each case, different equa-tions can be used to describe the electrode geometry to account for the current flow through the material/device. Use of the wrong equation or not being aware of the limits of these equations for specific geometries can result in erroneous values being extracted. Here we use an in-house built Finite Element Analysis Package (Elcer) to simulate the electrical response of electroceramics using a number of electrode geometries, including full surface electrodes and micro-contacts. Different equations are tested to determine the accuracy of each equation for each electrode geometry. The limita-tions of these equations will be discussed with reference to simulated current density plots, aiding visual understanding.

5:00 PM(EAM-ELEC-S9-009-2018) Finite Element Modelling of the Electrical Microstructure of Rough InterfacesJ. P. Heath*1; J. S. Dean1; J. Harding1; D. C. Sinclair1

1. University of Sheffield, Material Science and Engineering, United Kingdom

Many key technologies for a sustainable future require the use of multi component layered architectures. Examples include solar cells and multi-layer ceramic capacitors and actuators. Producing these devices in an industrially acceptable time scale means that it is inevitable that interfaces between different materials will not be perfect. Pores and interface roughness will be present. In general, such interfaces are assumed to be detrimental to device performance and require further investigation. Here we use an in-house built Finite Element Analysis package to perform 3D simulations of rough ceramics/electrode interfaces and generate their corresponding impedance spectra. Using prior knowledge of the interface geom-etry, material properties and observations of current flow; we have developed a method for fitting the impedance response of various rough interfaces. Using the example of an analytical method used to fit a rough interface approximated by a simple repeating pattern we have developed a statistical based method for fitting the impedance response of a realistic randomised rough interface where equivalent circuit parameters are derived from the interface’s profile. Here we will detail the fitting procedure and the conditions that it is valid.


Abstracts


Refined Synthesis Routes to Advance and Enable Properties IRoom: Cypress A/BSession Chair: Mark Losego, Georgia Institute of Technology

2:00 PM(EAM-ELEC-S10-007-2018) Disorder and fluctuations in superconducting BaPb1-xBixO3 epitaxial thin films (Invited)D. T. Harris*1; N. Campbell2; R. Uecker3; D. Schlom4; M. Rzchowski2; C. Eom1

1. University of Wisconsin-Madison, Materials Science and Engineering, USA

2. University of Wisconsin - Madison, Physics, USA3. Leibniz Institute for Crystal Growth, Germany4. Cornell University, Department of Materials Science and Engineering,

USA

Recent predictions of a wide-gap topological insulating state in BaBiO3 has stimulated significant interest, in part because BaBiO3 hosts superconductivity. The simultaneous existence of these two quantum phases in an oxide is ideal for synthesizing heterostruc-tures that enable study of Majorana physics or engineering new high temperature superconducting phases. However, few reports exist showing the high quality typical in other oxide epitaxial films. Here we demonstrate that the large lattice constant of BaBiO3 materials (apc≈ 4.3 Å) limits quality in thin BaPb1-xBixO3 (BPBO) supercon-ducting films when grown on the commonly used SrTiO3 substrate (apc≈ 3.9 Å). Thick BPBO films exhibit bulk like transition tempera-ture (~11 K) and the lowest reported resistivity; however, transition temperatures are significantly depressed with decreasing thickness, consistent with a disorder induced superconductor-insulator tran-sition. By moving to LaLuO3 substrates (apc≈ 4.18 Å) with better lattice matching, thin BPBO exhibit higher superconducting transi-tion temperatures, smoother surfaces, and higher crystal quality. The sensitivity of BPBO to disorder caused by poor lattice matching is an important consideration as the community attempts to design new properties using thin heterostructures. This work supported with funding from the DOE Office of Basic Energy Sciences under award number DE-FG02-06ER46327.

2:30 PM(EAM-ELEC-S10-008-2018) Domain switching in epitaxial ferroelectric HfO2 filmsT. Shimizu*1; T. Mimura1; T. Kiguchi2; T. Shiraishi2; A. Akama2; T. J. Konno2; O. Sakata3; K. Yoshio3; H. Funakubo1

1. Tokyo Institute of Technology, Japan2. Tohoku University, Japan3. National Institute for Materials Science (NIMS), Japan

Ferroelectric HfO2-based thin films gather much interest due to their compatibility to Si-based technology. Mature manufacturing processes are expected to realize novel ferroelectric and piezoelec-tric devices with HfO2-based ferroelectric thin films. Most study in HfO2-based ferroelectrics have used polycrystalline films annealed after deposition by atomic layer deposition, chemical solution depo-sition, and sputtering techniques. Their random orientations of polycrystalline films make difficult to access crystallographic infor-mation, hence the study with epitaxial thin films is highly demanded. In this study, we perform growth of YO1.5-substituted HfO2 epitaxial films on yttria-stabilized zirconia (YSZ) substrates by using pulsed laser deposition techniques. Careful phase identification examined by x-ray diffraction and transparent electron microscopy showed

7% YO1.5-substituted HfO2 films have polar orthorhombic structure. Moreover, we observed domain structure in Y substituted HfO2 film. Furthermore, this domain structure can be switched by an appli-cation of electric field. This domain switching leads ferroelectric hysteresis in these films.

2:45 PM(EAM-ELEC-S10-009-2018) Thickness Dependence of Pyroelectric and Ferroelectric Response in (Hf,Zr)O2

S. W. Smith*1; M. D. Henry1; J. Ihlefeld2

1. Sandia National Laboratories, USA2. University of Virginia, Department of Materials Science and Engineering,

USA

(Hf,Zr)O2 is a recently-discovered ferroelectric that can be prepared as a thin film by atomic layer deposition. (Hf,Zr)O2 is unusual because it’s ferroelectric response comes from a meta-stable orthor-hombic phase most often observed in thin films – <~30 nm thick – a scale unusual for conventional ferroelectrics. Still, like conven-tional ferroelectrics, the ferroelectric response in (Hf,Zr)O2 films is expected to degrade as the film thickness approaches that of the unit cell. In this work we show the polarization response of (Hf,Zr)O2 films decreases with thickness, from a remanent polarization of 17 µCcm-2 at 20 nm down to 3 µCcm-2 at 5 nm, while the pyroelec-tric coefficient increases from 25 µCm-2K-1 to 45 µCcm-2K-1 at these respective thicknesses. These room temperature responses and addi-tional values measured at elevated temperatures, provide insight to the impact of thickness on the stability of the orthorhombic ferro-electric phase and phase transition in (Hf,Zr)O2. Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.

3:00 PM(EAM-ELEC-S10-010-2018) Domain Wall Contribution to Room Temperature Phonon Scattering in Epitaxial PbZr0.20Ti0.80O3 on SrTiO3

E. A. Paisley*1; B. M. Foley4; J. Gaskins4; D. Scrymgeour1; J. Michael1; B. McKenzie1; D. Medlin1; J. Maria2; P. E. Hopkins4; J. Ihlefeld3

1. Sandia National Laboratories, USA2. North Carolina State University, Materials Science and Engineering, USA3. University of Virginia, Department of Materials Science and Engineering,

USA4. University of Virginia, Mechanical and Aerospace Engineering, USA

Recently, our group showed that ferroelastic domain walls in ferro-electric thin films scatter phonons at room temperature. Through the application of an electric field, the domain structure is modified, enabling thermal conductivity tuning. In this presentation, we will focus on the mechanism of 90° domain wall density and scaling to thermal transport in PZT. Epitaxial 001-oriented PbZr0.20Ti0.80O3 films, with thicknesses of 25 nm to 200 nm, are prepared on SrTiO3 through pulsed laser deposition. Transmission electron microscopy and X-ray diffraction show dense, epitaxial film stacks. Hysteresis loops of the Pt|(20/80) PZT|SRO|STO stack display clear polariza-tion saturation with low leakage contributions and piezoresponse force microscopy and scanning electron microscopy charac-terize the 90° domain wall density for the thickness series. We will discuss the role of domain boundaries on thermal properties, where time domain thermoreflectance (TDTR) is used to extract Kapitza conductance across 90° domain walls as a function of PZT thickness and 90° domain density. Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.


Abstracts

Refined Synthesis Routes to Advance and Enable Properties IIRoom: Cypress A/BSession Chair: Sean Smith, Sandia National Laboratories

4:00 PM(EAM-ELEC-S10-011-2018) Novel plasmonic metamaterials enabled by epitaxial CdO multilayer heterostructures (Invited)K. Kelley*1; J. Maria1; E. Runnerstrom1; E. Sachet1


In recent years, conductive oxides have been increasingly inves-tigated in the context of plasmonics. While plasmonic materials for UV-VIS and near infrared wavelengths have been found, the mid-infrared range remains a challenge to address. Recent develop-ments show Y-doped (CdO:Y) and In-doped CdO (CdO:In) grown via RF assisted reactive high power impulse magnetron sputtering (HiPIMS) can achieve electron mobilities (~400 cm2V-1s-1) and carrier densities (1020 cm-3) that satisfy the criteria for mid-infrared spectrum plasmonics, and overcome the losses seen in conven-tional plasmonic materials, such as noble metals. In this work, we identify several candidate dopants with this relatively new depo-sition technique. Furthermore, we show that epitaxial films grown by this method affords the ability to reproducibly tune the electron carrier densities between low 1019 and mid 1020 concentrations by controlling the magnetron power and the cathode to substrate distance for the dopant source. In regard to plasmonics, these electron carrier concentrations allow us to access light-matter inter-actions (i.e. plasmon polaritons) in the 2 µm to 5 µm range, which are thoroughly discussed in this presentation. HiPIMS in conjunc-tion with doped CdO as model metameterial offer a more accessible route towards ubiquitous IR plasmonic technologies.

4:30 PM(EAM-ELEC-S10-012-2018) Quantifying the Processing Kinetics of Vapor Phase Infiltration for Organic-Inorganic Hybrid Materials SynthesisM. D. Losego*1; C. Leng1


Vapor phase infiltration (VPI) is an emerging processing tech-nology for infusing polymers with inorganic constituents to create new organic-inorganic hybrid materials with novel electrical, chemical, and/or physical properties. These new materials can have applications as chemical barriers, filtration media, or photo-lithographic hard masks. Here, the focus is to better understand the process science of VPI to create a pathway for rational design of material composition and structure. In this study, we use the model system of poly(methyl methacrylate) (PMMA) exposed to trimethylaluminum (TMA) gaseous precursors to demonstrate an approach for extracting activation energies for both precursor diffusion and reaction within a polymer. We demonstrate that Fick’s 2nd Law has two useful solutions that can be fit to different types of data: either total mass uptake with time or concentration profiles as a function of distance. Using either approach, effective diffusion coefficients can be measured as a function of temperature and fit to an Arrhenius model to extract activation coefficients. For the case of PMMA-TMA, which is known to undergo a chemical reactions, a change in the Arrhenius slope is observed and can be assigned to the free energy of the reaction equilibrium. Using this approach, the VPI process kinetics can be fully understood for any precursor-polymer couple.

4:45 PM(EAM-ELEC-S10-013-2018) Development of lattice-matched Mg1-xCaxO gate oxides for (Al)GaN power transistorsP. Dickens*4; E. A. Paisley3; B. Gunning3; S. W. Smith5; M. Brumbach3; S. Atcitty3; M. D. Losego1; J. Maria2; J. Ihlefeld6

1. Georgia Institute of Technology, School of Materials Science and Engineering, USA

2. North Carolina State University, Materials Science and Engineering, USA3. Sandia National Laboratories, USA4. Sandia National Laboratories, 1816, USA5. Sandia National Laboratories, Electronic, Optical, and Nano

Materials, USA6. University of Virginia, Department of Materials Science and

Engineering, USA

The development of wide bandgap (WBG) transistors is an active area of research for next generation power electronics owing to the promise of higher breakdown field, thermal conductivity, and saturated electron velocity over traditional silicon insulated gate bipolar transistors. Currently however, the improvement of WBG transistors is limited by poor gate oxide performance, which leads to normally-on operation, high leakage currents, and frequency dispersion. Ultimately, gate oxide performance is determined by the conduction band offset to the WBG material as well as the chemical and structural quality of the interface. Thus, alloys of magnesium oxide and calcium oxide (MCO) are promising candidates for gate insulators for (Al)GaN owing to their wide bandgap, high dielec-tric constant and ability to lattice-match directly to (Al)GaN. In this presentation we will show our recent efforts in understanding the effect of (Al)GaN substrate doping (5x1016 cm-3 and 2x1018 cm-3) on MOS-capacitor electrical performance. We will show gate oxide performance metrics—interface state density, gate leakage currents, and frequency dispersion response—for lattice-match MCO compared to atomic layer deposited alumina.

5:00 PM(EAM-ELEC-S10-014-2018) High Entropy Ultra-High Temperature Thin Films: Synthesis and CharacterizationT. M. Borman*1; M. D. Hossain1; Z. Rak1; D. Brenner1; T. Harrington3; K. S. Vecchio3; E. A. Paisley2; J. Maria1

1. North Carolina State University, Materials Science and Engineering, USA2. Sandia National Laboratories, USA3. University of California, San Diego, Department of NanoEngineering, USA

The authors describe the use of a 5-cathode reactive RF magnetron sputtering system to fabricate up to 5-component refractory high entropy carbides which form a robust class of high temperature materials. Thin films of mixed carbides consisting of the following elements: Ti, Zr, Hf, Nb, Ta, Mo, and W, will be discussed. All films are sputtered reactively in a gas atmosphere of Ar with methane as the carbon source. Use of 5 cathodes allows for rapid exploration of the 5 metal composition space in short time spans. A broad range of metals can be incorporated into single-phase rocksalt structures across temperatures from room temperature to 900°C, although substrate interactions must be considered. Furthermore, despite challenges with integrating W and Mo into a rocksalt carbide struc-ture using bulk processing, both elements are readily incorporated into the structure in thin film form. It is suspected that the high kinetic energy of the incoming adatoms provides adequate kinetic energy to form and quench rocksalt phases. The structural quality and uniformity of the thin films and sharp, clean interfaces between layers of different compositions can allow for characterization of the thermal properties and stability of these new materials including thermal transport and chemical diffusion in elevated temperatures. This can prove valuable in developing compositions to withstand elevated temperatures.


Abstracts

5:15 PM(EAM-ELEC-S10-015-2018) Evidence for Entropy Stabilization in Oxide Thin Film GrowthG. N. Kotsonis*1; C. M. Rost2; D. T. Harris3; J. Maria1

1. North Carolina State University, Materials Science and Engineering, USA2. University of Virginia, Mechanical and Aerospace Engineering, USA3. University of Wisconsin - Madison, Materials Science and

Engineering, USA

Thin films of the composition MgxNixCoxCuxZnxScxO (x~0.167) were grown to test a hypothesis that the condensation of energetic species can contribute to the entropic stabilization of many- component solid solutions that are inaccessible via equilibrium routes. To do so, a series of experiments that modulate incident particle kinetic energy and laser plasma oxidation power during thin film growth are presented. The data set suggests that deposition condi-tions supporting high kinetic energy adatoms contribute to entropic stabilization of a single phase, while conditions that are highly oxidizing favor phase separation. These findings are consistent with the interpretation that the effective temperature of incoming adatoms contributes to the TS free energy product; and that it may be possible to stabilize a broader spectrum of multicomponent oxides into a single-phase solid solution using energetic deposition techniques.

5:30 PM(EAM-ELEC-S10-016-2018) Underlying Mechanisms Controlling Thermal Properties in Entropy Stabilized Oxide Thin FilmsC. M. Rost*1; J. L. Braun1; G. N. Kotsonis2; D. T. Harris3; J. Maria2; P. E. Hopkins1

1. University of Virginia, Mechanical and Aerospace Engineering, USA2. North Carolina State University, Materials Science and Engineering, USA3. University of Wisconsin Madison, Materials Science and

Engineering, USA

Entropy-stabilized oxides (ESOs) demonstrate the viability of novel materials engineering using configurational entropy to drive phase stabilization. The prototype ESO, MgxNixCoxCuxZnxO (J14), where x=0.2, exhibits a rocksalt structure where cations are distrib-uted randomly on one FCC sublattice with minimal positional disorder, and an interleaved FCC anion sublattice with oxygen ions displaced to accommodate distortions in the cation polyhedra. Using time domain and frequency domain thermoreflectance (TDTR/FDTR), we measure thermal conductivity of J14 for comparison with other, less disordered compositions containing the same constitu-ents and more disordered 6-component thin film systems (J14+X, where X = Cr, Ge, Sc, Sn, or Sb). Thermal conductivity decreases with increasing configurational disorder, approaching the minimum limit, which is typically reserved for amorphous phases. Results are discussed in terms of various scattering mechanisms including mass, strain, and volume effects, emphasizing understanding of thermal properties from a local structural perspective. In this talk we focus on the experimental process of elimination using several metrology techniques in conjunction with TDTR/FDTR to gain a meaningful, structure-property perspective on the thermal properties of these metastable, configurationally disordered, and highly crystalline systems.


Superconducting Materials IIRoom: Citrus ASession Chair: Timothy Haugan, U.S. Air Force Research Laboratory

2:00 PM(EAM-ELEC-S11-007-2018) High-throughput syntheses and fast screening of cuprate and FeSe thin films (Invited)K. Jin*1

1. Institute of Physics, Chinese Academy of Sciences, National Lab for Superconductivity, China

In this talk, I will present our recent results on electron-doped cuprate as well as FeSe superconductors. To get an electronic phase diagram in a more efficient way, we employed the high-throughput synthesis techniques to deposit the so-called combinatorial films. The combinatorial laser MBE was used to fabricate electron-doped cuprate thin films (La2-xCexCuO4). On a single substrate of 1 cm in length, we succeeded in obtaining a composition gradient from x = 0.10 to x = 0.19, spreading from the optimally doped supercon-ducting phase to the heavily overdoped Fermi liquid phase. On the basis of sufficient electrical transport data in high space resolution, an quantitative relation between the doping level and the supercon-ducting transition temperature (Tc) was able to be identified for the first time. By carefully manipulating the distribution of the laser energy, we can grow high-quality FeSe films with a gradient Tc from 14 K to less than 2 K on a single chip. A systematic study of structure and transport was performed and the factors relevant to the super-conductivity will be discussed. Finally, I will briefly introduce the MGI (Materials Genome Initative) center in Beijing, where we are eager to see the advantages of high-throughput experiments in the field of superconductivity research.

2:30 PM(EAM-ELEC-S11-008-2018) Growth of atomically flat NbN thin films and development of in situ two-coil mutual inductance technique (Invited)J. Jia*1

1. Shanghai Jiao Tong University, Physics and Astronomy, China

High quality superconducting NbN thin films with atomic flatness have been grown on Nb-doped SrTiO3 (111) substrate by plasma–assisted molecular beam epitaxy for the first time. Using scanning tunneling microscopy and in situ reflection high energy electron diffraction, we investigate the surface structure of epitaxial NbN thin films on the SrTiO3 (111) substrate. Single crystal NbN (111) films are obtained at substrate temperature above 1000K. The quality of the as-grown films can be further improved by annealing at elevated temperatures. The atomic structure of the NbN (111) surface is observed with STM for the first time. In the second part of this talk, I will report the development of both transmission and reflection two-coil mutual inductance techniques for in situ measurement of the diamagnetic response of a superconductor. We demon-strate the performance of the two-coil mutual inductance setup on a 10-nm-thick NbN thin film grown on a Nb-doped SrTiO3(111) substrate. This technique is very useful for studying superconducting thin films.


Abstracts

3:00 PM(EAM-ELEC-S11-009-2018) Manipulation of micro-strain to generate strong and isotropic artificial pinning centers in YBCO nanocomposite films (Invited)J. Wu*1

1. University of Kansas, USA

Strong and isotropic artificial pinning centers (APCs) are critical to provide optimal pinning and therefore high critical current density Jc in layered-structured high-Tc superconducting YBa2Cu3O7-x (YBCO) thin films and coated conductors for practical applications. Controllable growth of nanoscale APCs with desired morphology, orientation and dimension is key towards this goal. Motivated by this, this work explores manipulation of micro-strain through double doping of the primary APC materials that tend to form c-axis aligned 1D APCs, such as BaHfO3 and BaZrO3, in presence of a secondary APC material of Y2O3 nanoparticles (3D APCs). We have found that the adaption of the 1D APCs is affected by their mechanical rigidity and mixed morphologies of 1D, 2D, 3D APCs can be obtained through adaption of the high concentration 1D APCs to the micro/local strain by Y2O3 3D APCs. Transport Jc measured on these samples revealed strong and isotropic pinning landscape at temperatures of 50-80K and field up to 9 T. Specifically, a significantly enhanced pinning force density Fp as well as almost no angular dependence on the magnetic field orientations can be obtained at optimal mixed APC morphologies and concentrations.

3:45 PM(EAM-ELEC-S11-010-2018) Comparison of the Flux Pinning Landscape of YBa2Cu3O7-δ Thin Films with Single and Mixed Phase Additions BaMO3 + Z: M = Hf, Sn, Zr and Z = Y2O3, Y2BaCuO5

M. Sebastian*1; T. Bullard4; C. Ebbing1; G. Panasyuk4; J. Huang5; C. F. Tsai5; W. Zhang5; H. Wang5; B. Gautum3; C. Shihong3; J. Wu3; T. J. Haugan2

1. UDRI, USA2. Air Force Research Lab, AFRL/RQQM, USA3. University of Kansas, Dept. of Astronmomy & Physics, USA4. UES, USA5. Purdue University, Dept. of Materials Engineering, USA

Addition of nanophase defects to YBa2Cu3O7-δ (YBCO) supercon-ductor thin films enhances flux pinning and increases transport current densities (Jct). While previous studies focused on single-phase additions such as BaSnO3, BaZrO3, and Y2BaCuO5 (Y211), the addition of several phases has shown strong improvements by combining different flux pinning mechanisms. This paper further explores the effect of mixed phase nanoparticle pinning, with the addition of insulating, nonreactive phases of: 1) BaSnO3 + Y2O3, 2) BaSnO3 + Y211, 3) BaZrO3 + Y2O3, and 3) BaHfO3 + Y2O3. Pulsed laser deposition produced films on LaAlO3 and SrTiO3 substrates at deposition temperatures of 750-840 °C. Magnetic current densities Jcm (H, T) for fields ranging from H = 0-9T with H // c and tempera-tures from 5-77 K, and transport angular current densities Jct (H, T, θ) for fields ranging from H = 1-5 T at 65 K are measured, providing a detailed picture of pinning effects. Optimized results of flux pinning, critical transition temperatures (Tc), lattice parameters, and microstructures are also presented. The temperature dependence of the current density, Jcm(T), is mathematically modeled to compare the isotropic weak and anisotropic strong pinning contributions for each system studied.

4:00 PM(EAM-ELEC-S11-011-2018) Comparison of edge-barrier pinning in micron scale YBCO bridges made by photolithography and ultrafast laser ablationK. Lange*1; J. Bulmer1; A. Di Bernardo2; J. Feighan2; T. J. Haugan3; W. O’Neill1; J. Robinson2; M. Sparkes1

1. University of Cambridge, Institute for Manufacturing, United Kingdom2. University of Cambridge, Department of Materials Science & Metallurgy,

United Kingdom3. US Air Force Research Lab, AFRL/RQQM, USA

The critical current density (Jc) of thin-film YBCO bridges can be significantly enhanced by edge-barrier pinning. Assuming a perfect edge, edge-barrier pinning effects bridges as large as 200 µm. This limit becomes smaller as edge quality degrades. Unlike photolithog-raphy, laser machining is a chemical free, flexible process; the use of an ultrafast laser (270 fs, 1030 nm) gives minimal edge damage. We measured Jc for 100 µm, 30 µm and 10 µm wide bridges, thick-ness 200 nm, made by both photolithography and ultrafast laser processes. For validation Raman spectra of films before and after heat treatments at 300°C and laser processing were used to calculate the oxygen content. The measured decrease in oxygen content could then be used as an indicator for laser processing induced heat effects; the effectiveness of material removal measured by EDS. In air mate-rial re-deposition and melt edges were observed when processing with a Gaussian beam profile. The results were then optimised by processing with flat top spatial intensities in vacuum. Finally, the cross-section area and the edge quality were examined using SEM and transport measurements.

4:15 PM(EAM-ELEC-S11-012-2018) Development of High-Energy-Density Superconducting-Magnetic-Energy-Storage (SMES) for Aerospace Applications (Invited)T. J. Haugan*2; T. Bullard1

1. UES Inc, U.S. Air Force Research Laboratory, USA2. U.S. Air Force Research Laboratory, USA

Electrical energy storage devices are critical components of every aerospace vehicle. They are needed for many functions, such as to provide high-power for pulsed loads, for emergency power during system failures, and as a high-capacity energy source for hybrid-electric-vehicle (HEV) propulsion. Electric propulsion for airborne vehicles is understood to provide significant energy effi-ciency benefits, including during taxiing, cruise, and other flight phases and regen power during descent. Superconducting-magnetic-energy-storage (SMES) devices offer attractive and unique features for airborne vehicles including ultra-high power densities of > 100 kW/kg for both charge and discharge, 100% storage efficiencies for unlimited times, and for some designs virtually no degradation for up to 10^8 charge/discharge cycles. Recent investigations indicate the mass-specific energy densities can reach > 100 Wh/kg and be competitive with Li-batteries. This paper will describe functions of SMES for aerospace applications, and provide a recent update on the development and performance of SMES devices being designed and built. In-house computation of the design of SMES devices optimized for mass-specific energy densities will be shown, and compared with devices presently existing or being developed.


Abstracts

4:45 PM(EAM-ELEC-S11-013-2018) Tunable Broadband Radiation Generated Via Ultrafast Laser Illumination of an Inductively Charged Superconducting RingT. Bullard*5; J. Bulmer3; M. Ferdinandus4; J. Murphy2; T. J. Haugan1

1. Air Force Research Lab, AFRL/RQQM, USA2. University of Dayton Research Institute, USA3. University of Cambridge, Department of Materials Science and

Metallurgy, United Kingdom4. Air Force Institute of Technology, USA5. UES Inc., USA

It is well established that superconducting materials will emit micro-wave/terahertz radiation when illuminated with a femtosecond infrared laser pulse. Typically this phenomena is examined by illu-minating a voltage biased superconducting thin film bridge. In this investigation an inductively charged superconducting thin film ring is considered. We believe the configuration lends itself to a simple compact microwave emitter device as the antenna plays the part of the waveguide and power supply, and contact heating between the current leads and the superconductor are now eliminated. We find that the emitted energy of this system displays a power-law depen-dence with increasing current, laser energy and illumination area, and shows a frequency dependence on the system dimension as well as a well-defined polarization direction. Results illustrate the rich and complex dynamics that span the optical, terahertz and micro-wave regimes.

5:00 PM(EAM-ELEC-S11-014-2018) Terahertz emission from the intrinsic Josephson junctions of high-symmetry thermally-managed Bi2Sr2CaCu2O8+δ microstrip antennas (Invited)R. A. Klemm*1

1. University of Central Florida, Physics, USA

We show for high-symmetry disk, square, or equilateral triangular thin microstrip antennas respectively obeying C∞v, C4v, and C3v point group symmetries that the transverse magnetic electomagnetic cavity mode wave functions are restricted in form to those that are one-dimensional representations of those respective point groups. Plots of the common nodal points of the ten lowest-energy non- radiating two-dimensional representaitons of each of these three symmetries are presented. For comparison with symmetry-broken disk intrinsic Josephson junction microstrip antennas constructed from the highly anisotropic layered superconductor Bi2Sr2CaCu2O8+δ (BSCCO), we present plots of the ten lowest frequency orthonormal wave functions and of the angular distributions of the emission power. New results for the regular hexagonal microstrip antenna are also presented. These combined results are compared with previous results for square and equilateral thin microstrip antennas.

5:30 PM(EAM-ELEC-S11-015-2018) Possible terahertz emissions from the intrinsic Josephson junction in thermally managed annular microstrip antennas of the Bi2Sr2CaCu2O8+δ

S. W. Bonnough*1; R. A. Klemm1

1. University of Central Florida, Physics, USA

We calculate the transverse magnetic electromagnetic cavity mode wave functions for a thin annular microstrip antenna with the ratio of the inner and outer ratios respectively, ρ1/ρ2, ranging from 0.1 to 0.9. We present representative plots of the lowest frequency wave functions and their corresponding angular emission powers.


Advanced Electronic Materials II: Ferroelectric MaterialsRoom: Orange CSession Chair: Zuo-Guang Ye, Simon Fraser University

2:00 PM(EAM-ELEC-S13-008-2018) Recent Developments in Relaxor-PT Piezoelectric Ceramics and Crystals (Invited)T. Shrout*1; F. Li1; D. Lin1; J. Luo2

1. Pennsylvania State University, USA2. TRS Technologies, INc., USA

The discovery of ultrahigh piezoelectricity in relaxor ferroelectric solid solution single crystals, e.g. PMN-PT, has led to their imple-mentation in high performance medical ultrasound transducers and underwater sonar. A key signature of relaxor-ferroelectrics is the existence of polar nano regions (PNRs), a nano-scale inhomogeneity that coexists with normal ferroelectric domains. The contribution of these local structures has been theoretically modeled to be the origin of the ultra-high piezo activity. Based on the paradigm, recent devel-opments have experimentally confirmed that modest changes in the polarizability of PNRS can be regarded as “seeds” to further enhance the piezoelectric activity of relaxor ferroelectrics. Both modified polycrystalline and single crystals have been shown to exhibit ultra-high piezo d33 coefficients. Furthermore, dielectric permittivities greater than 10,000 and relatively good temperature stability have been achieved. The impact of these property improvements on applications, including ultrasound transducers and sensors, will be presented.

2:30 PM(EAM-ELEC-S13-009-2018) Multiferroic Morphotropic Phase Boundaries and Related Properties in BiFeO3-Based Solid Solutions (Invited)Z. Ye*1

1. Simon Fraser University, Canada

The presence of morphotropic phase boundary in ferroelectric solid solutions (FE-MPB) is known to be crucial for high piezoelectricity. Similarly, magnetic MPB (M-MPB) is found in a few ferromag-nets and is proved to be greatly beneficial to the magnetostricitive response. One naturally asks if in multiferroics that exhibit both ferroelectricity and magnetism, the FE-MPB and M-MPB could exist simultaneously, and if so, what the relation between these two kinds of MPB would be, and how they would affect the properties. In this paper, we report the studies of ferroelectric and magnetic double morphotropic phase boundaries in BiFeO3-based multiferroics. A comprehensive ferroelectric-magnetic phase diagram is estab-lished in terms of temperature and composition, which depicts the coexistence of a FE-MPB and a FM-MPB. These two kinds of MPBs overlap with each other. Such unusual coincidence of both magnetic MPB and ferroelectric MPB, the so-called double MPB, points to new kinds of couplings among the multiple physical quantities so that such effects as magnetoelectricity, magnetostrictive and piezo-electricity, could be enhanced near the overlapping MPB region. In addition, we find an unusual magnetic pole inversion behavior in mutiferroic (1-x)BiFeO3-xDyFeO3 solid solution which can be tuned by varying the composition.


Abstracts

3:00 PM(EAM-ELEC-S13-010-2018) Stabilization and Sintering of Pb(In1/2Nb1/2)O3-Pb(Zn1/3Nb2/3)O3-PbTiO3 CeramicsM. J. Brova*1; B. H. Watson1; Y. Chang1; E. R. Kupp1; J. Wu1; M. A. Fanton2; R. J. Meyer2; G. L. Messing1

1. The Pennsylvania State University, Material Science and Engineering, USA

2. The Pennsylvania State University, Applied Research Laboratory, USA

An important limitation of many high performance relaxor-based ferroelectric materials is the operating temperatures. The recently developed Pb(In1/2Nb1/2)O3-Pb(Zn1/3Nb2/3)O3-PbTiO3 perovskite solid solution has shown high thermal stability while also possessing a large piezoelectric charge coefficient. There is little understanding about the phase stability and sintering of Pb(In1/2Nb1/2)O3-Pb(Zn1/3Nb2/3)O3-PbTiO3. This work investigated phase formation of perovskite powder prepared by the Columbite approach, and its sinterability. Stoichiometric calcinations resulted in perovskite and zinc-based pyrochlore at all conditions. The addition of excess zinc oxide led to accelerated reaction kinetics and substantially increased perovskite concentration and densification.

3:15 PM(EAM-ELEC-S13-011-2018) Hard-Piezoelectric Ceramics for Low Temperature Co-Fired Multilayer Piezoelectric TransformersS. Dursun*1; A. Gurdal3; S. Tuncdemir3; C. Randall2

1. Pennsylvania State University, Materials Research Institute, USA2. Pennsylvania State University, Materials Science and Engineering, USA3. Solid State Ceramics, Inc., USA

Hard-piezoelectric ceramics have been widely used high power applications such as ultrasonic motor, actuators and piezoelec-tric transformers (PT’s). These piezoceramics typically have high sintering temperatures (~1200°C). Since the temperatures are high, co-firing metallization is pretty much limited to quite expensive plat-inum (Pt), unfortunately. Electrode materials alternative to Pt would bring down the cost significantly and improve the performance due to decreased electrical losses. PNN-PMW-PZT system to apply for high-power piezoelectric actuators. These compositions satisfactory for multilayer PT’s due to high sintering temperatures by flux mate-rials were added to decrease the sintering temperature to or below 1000°C. Base metal electroding (e.g., Cu and Ni) is the cheapest option for multilayer applications. Cu was chosen as the base metal option. Yet, Cu oxidizes under conventional sintering conditions. Reducing atmosphere is needed to keep Cu in the metallic form. Therefore, material properties under reducing conditions will also be discussed.

Reliability of Electronic Materials and DevicesRoom: Orange CSession Chair: Matthew Cabral, North Carolina State University

4:00 PM(EAM-ELEC-S13-012-2018) Complexity of Test for Non-linear Components and SystemsJ. T. Evans*1

1. Radiant Technologies, Inc., USA

The majority of electronic components manufactured today have linear properties. Test procedures in production consist of simple algorithms that determine if the component meets performance targets since that performance will remain constant over a life-time. Reliability evaluation only requires operating the device until it physically fails. Non-linear materials greatly complicate the test environment. The performance of these materials is very sensitive to small changes in fabrication processes. Remanent polarization adds a second layer of complexity. Non-linear devices remember everything that happens to them over their lifetime so end-of-life is

dependent on their history of use. Product designers cannot know beforehand the historical trajectory each device will follow so he or she must allow for wider variances in component performance while still guaranteeing system operation. To support this expanded design requirement, test engineers must be able to replicate any history expected for the devices and systems under production. The library of test procedures must be extensive and test procedures must be able to interact with each other as a test progresses. Radiant Technologies defines this characteristic as Complexity of Test. The author will propose definitions and identify levels of complexity for testing ferroelectric capacitors arising from experience with ferro-electric tester design.

4:15 PM(EAM-ELEC-S13-013-2018) Effects of Boundary Conditions on Resistance Degradation of SrTiO3

D. Long*1; B. Cai1; E. C. Dickey1


As capacitor devices are pushed to smaller dimensions it becomes increasingly important to understand the time-dependent resistance degradation process in order to maximize device reliability. Here we report on the modulation and control of the degree and rate of resistance degradation in undoped and iron doped SrTiO3 single crystal systems as it relates to the electrode boundary conditions. The dielectric preparation varies from high quality mechanochem-ical polishing to a diamond lapping film polish which affects the subsurface dislocation density and surface roughness. The elec-trode porosity is varied by changing the angle of incidence during sputter deposition, which changes the permeability of oxygen across the electrode. Marked differences are observed in the degradation behavior depending on the dielectric surface preparation and elec-trode microstructure. Utilizing in-situ electrical measurements we monitor the degradation as it relates to the interface boundary conditions. Experiments in O-18 enriched atmospheres coupled with SIMS analysis are used to investigate oxygen exchange across the electrode and transmission electron microscopy and electron energy loss spectroscopy are used to study local chemistry and struc-ture in the near interface region. Funding for this work provided by AFOSR grant FA9550-14-1-0067.

4:30 PM(EAM-ELEC-S13-014-2018) Hygroscopic and Piezoelectric Properties of KNN-based CeramicsM. Zhuk*1; J. Glaum1; M. Einarsrud1

1. Norwegian University of Science and Technology, Department of Materials Science and Engineering, Norway

Piezoelectric materials are an indispensable element in a large range of technical applications in the fields of electrical, electronic, medi-cine, robotics, ultrasonic, space-industries and many others. Over the past.years intensive research has been carried out, aimed to replace the lead-based compounds that have been dominating the world market for the last decades. The search for new alternatives was arisen due to tightening of environmental regulations and well-known hazardous effect of lead and lead oxides. Among the lead-free piezoelectric systems, potassium sodium niobate KxNa1-xNbO3 (KNN) is one of the most promising and well-studied candidates. However, the hygroscopic nature of many of the alkali precursors as well as the final compound itself, still constitutes a major challenge for reliable processing and usage of this material. We investigated and compared the effect of different dopants on the piezoelec-tric properties and hygroscopicity of KNN ceramics. For that, the release of ions was monitored while soaking the samples in aqueous medium for 30 days. We observed the prevailing release of A-site cations as well as degradation of the piezoelectric characteristics.


Abstracts

4:45 PM(EAM-ELEC-S13-015-2018) Impact of porosity on piezoelectric and mechanical performance of BaTiO3 ceramicsK. Skaar Fedje1; M. Einarsrud1; J. Glaum*1

1. Norwegian University of Science and Technology NTNU, Materials Science and Engineering, Norway

The ability to convert an electrical field into a mechanical pertur-bation and vice versa makes piezoelectric materials fundamentally interesting object of study as well as versatile components for indus-trial applications. Piezoelectric materials can serve as sensors and actuators in a range of fields covering vibration control in airplanes, ultrasound applications in submarines and medical devices or pickups for musical instruments. While for many piezoelectric applications the presence of porosity would be detrimental, in some cases – such as for medical or marine ultrasound devices as well as for energy harvesting systems – porosity and pore morphology are used to optimize device performance. However, the associated larger surface area makes the materials more prone to chemical reactions with the environment, which can degrade the long-term stability of the desired performance. In the present study, we investigate the influence of porosity on the piezoelectric and mechanical proper-ties of barium titanate ceramics. Different pore formers were used to create pores of different size and shape. The samples were soaked in saline solution and the change in properties was recorded over the course of two weeks. Both piezoelectric and mechanical proper-ties were found to degrade with increasing porosity. However, the soaking procedure had little influence on these characteristics.

Poster SessionRoom: Orange A/B

5:30 PM

(EAM-P001-2018) Electric-field assisted bonding of YSZ/alumina bilayersC. Grimley*1; A. Prette2; J. Schwartz3; E. C. Dickey1

1. North Carolina State University, Materials Science and Engineering, USA2. Lucideon, United Kingdom3. Pennsylvania State University, Department of Engineering Science and

Mechanics, USA

In the last few years, there has been a growing interest in applying flash sintering to multiphase samples and geometries, including multilayer stacks and 3D composites. Open questions include whether the inhomogeneity of point defects and chemical species at a biphasic interface affect the onset or effectiveness of the flash sintering process, and if the constraint between bodies with different sintering rates is alleviated by field-induced plasticity. These ques-tions are particularly relevant in layered applications like thermal barrier coatings (TBCs) where a clean bond and high adhesion dramatically effect the coating performance and lifetime. Here, we present the early results of a study investigating adhesion improve-ment via flash sintering between materials found in standard TBC systems: 8YSZ and α-alumina. The powders were contacted in bulk, creating a bilayer of green bodies which can be produced in multiple orientations. Processing parameters, including electric field magni-tude, orientation, and current density, were varied. The electrical behavior during flash was evaluated for interaction between the layers i.e. effects of electrical inhomogeneity. SEM and EDS were used to examine spatial densification differences in each layer and any interdiffusion between them.

(EAM-P002-2018) Ab-initio electrochemistry of transition-metal interfacesS. Mula*1; V. Kolluru1; K. Mathew1; R. G. Hennig1

1. University of Florida, Materials Science and Engineering, USA

The study of electrochemical interfaces is crucial in improving the performance characteristics of batteries and catalysts. The ab-initio study of these systems requires an appropriate treatment of the solid/electrolyte interfaces. For this, a solvation model called VASPsol was developed, which models the electrode part of the interface at density functional theory (DFT) level and represents the electrolyte part through an implicit model based on the Poisson-Boltzmann equation. In this work, this solvation model is being utilized to study the effect of electrolyte and applied electric potential on the surface energies of (100), (110) and (111) facets of platinum and copper electrodes. We find that the calculated electrode potentials of zero charge for Pt and Cu are close to the experimental values. We calculate adsorption energies and other defect energies such as step, kink, and vacancy for these facets in Pt and Cu electrodes to provide insight into the interfacial structure and processes for elec-trochemical etching and metal deposition.

(EAM-P003-2018) Electrocaloric effect, dielectric, ferroelectric and piezoelectric properties in normal and relaxor phases of La-doped PZT(65/35)S. Samanta*1; V. Sankaranarayanan1; K. Sethupathi1

1. Indian Institute of Technology Madras, Department of Physics, India

Here, we report the change in electrocaloric effect (ECE) due to the change in doping concentration of La in PZT. In order to do this, PZT (65/35) with La 6 - 9 % are prepared using alkoxide route of sol-gel synthesis, followed by heat treatment at 700 °C. Samples are sintered using a specially designed double atmospheric layer protected sintering method to protect lead loss at high temperatures. The morphological study and phase confirmation are carried out using scanning electron microscopy and X-ray diffraction respectively. The dielectric measurements are done in the frequency range from 100 Hz to 10 MHz at different temperatures from -50 °C to 300 °C. Polarization (P) vs. electric field (E) measurements are carried out in the required temperature range to calculate the ECE. The rela-tion between strain and relative permittivity with electric field are analyzed from P-E measurements. The piezoelectric properties are also studied at room temperature. High value of ECE in the vicinity of room temperature is desirable for practical applications. For a material, ECE is highest around its Curie temperature. The Curie temperature of the PZT (65/35) is found to decrease with increasing La concentration, which in turn makes the material more suitable for refrigeration and other applications near room temperature.

(EAM-P004-2018) Effect of Mn-addition on broadband dielectric properties of PMN-10PT ceramicsR. Katiliute1; M. Ivanov*1; M. Vrabelj2; L. Fulanovic2; A. Bradesko2; Z. Kutnjak2; B. Malic2; J. Banys1

1. Vilnius University, Lithuania2. Jozef Stefan Institute, Slovenia

Relaxor-based solid solutions, especially the ones with lead tita-nate as the second member, have a lot of potential applications due to their exceptional properties: piezoelectric, high dielectric permit-tivity, electrocaloric effect, etc. These are due to various mechanisms, including high mobility of domain walls and presence of polar nano regions or ferroelectric nanodomains. The 0.9Pb(Mg1/3Nb2/3)O3–0.1PbTiO3 (PMN-10PT) relaxor ferroelectric ceramics exhibit large dielectric permittivity anomaly and a phase transition to the ferroelectric state in the vicinity of room temperature. These proper-ties make it a good candidate to study influence of various dopants on functionalities. Manganese is a nice candidate to study, as it can be incorporated isovalently, ant it is known to significantly reduce dielectric losses and electrical conductivity in lead-based perovskites.


Abstracts

We studied the influence of Mn doping on dielectric properties of high density (>95%) PMN-10PT ceramics by means of broadband dielectric spectroscopy in 20 Hz – 40 GHz range using flat capacitor (low frequencies), coaxial lines and waveguides (microwave range). The Mn-addition significantly decreases the dielectric permittivity and losses with strong indication of suppression of domain wall movement and mobility of polar nanoregions. Various relaxational processes were resolved and will be discussed during the presentation.

(EAM-P005-2018) Dielectric Response of the Methylammonium Lead Halide Solar Cell AbsorbersI. Anusca3; S. Balciunas1; P. Gemeiner2; S. Svirskas1; M. Sanlialp3; G. Lackner3; C. Fettkenhauer3; J. Belovickis1; V. Samulionis1; M. Simenas1; E. Tornau4; M. Ivanov1; B. Dkhil2; J. Banys*1; S. V. Vladimir3; D. C. Lupascu3

1. Vilnius University, Lithuania2. CentraleSupelec CNRS-UMR8580 Université Paris-Saclay, France3. University of Duisburg-Essen, Germany4. Center for Physical Sciences and Technology, Lithuania

Hybrid organic–inorganic perovskites have recently attracted over-whelming attention due to their excellent photovoltaic performance yielding efficiencies well exceeding 20%. This has been related to properties such as long charge carrier lifetime, the exceptionally large diffusion length, large absorption coefficient, high carrier mobilities, large open-circuit voltages, and direct band gap. The organo-lead-trihalide perovskite compounds, CH3NH3PbX3, are the forerunners in efficiency. We address the key role of the dynam-ical nature of MA dipoles by combining large frequency range and temperature-dependent dielectric measurements with ultrasonic. Dielectric measurements were performed between temperatures 100 and 300 K and frequencies 102 –1011 Hz utilising a HP 4284A precision LCR meter, Agilent 8714ET vector network analyzer with a sample-terminated coaxial line and rectangular waveguide system with an Elmika scalar network analyser R2400. All measurements were performed at a rate of 1 K min−1. We show that a sufficiently high dielectric constant exists across the entire frequency range allowing for efficient screening of charged entities. This is the funda-mental effect facilitating the diffusion of photogenerated carriers. Furthermore, measurements are complimented by Monte Carlo simulations to show the antipolar nature of the structural phase transitions.

(EAM-P006-2018) Enhanced Curie temperature and piezoelectric properties of Sn doped (x)(Ba0.82Ca0.13Sn0.05)TiO3 – (1-x) Ba(Zr0.15Ti0.85)O3 perovskite systemV. Sarangi*1; A. Pramanick1

1. City University of Hong Kong, Materials Science and Engineering, Hong Kong

Piezoelectric ceramics are used as electromechanical transducers in many applications such as sonars, actuators, ultrasonic trans-ducers. Due to the toxicity of lead (Pb) and its detrimental effects to the environment, it is preferable to replace lead (Pb) in commer-cial piezoelectric ceramics. (Ba,Ca) (Zr,Ti)O3 or BCZT has been proposed as a possible alternative to Pb-based piezoceramics such as PZT. Despite the fact that (Ba,Ca) (Zr,Ti)O3 system exhibit large piezoelectric properties, their potential applicability is limited by low curie temperatures (i.e., TC ~60 °C). In order to overcome this limitation of BCZT ceramics, we have constructed a new system of (x)(Ba Ca Sn) TiO3 - (1-x) Ba(Zr Ti)O3 perovskite solid solution, which exhibit an improved curie temperature TC of up to ~100 °C. The introduction of tin (Sn+2) at the A-site, leads to formation of a broad morphotropic phase boundary (MPB) region with coexisting rhombohedral and tetragonal phases. The volume fractions of rhom-bohedral and tetragonal phases changes with x in the MPB region. In this work, we investigated the correlations between the different crystallographic phases present and the dielectric, piezoelectric and ferroelectric properties of the (x)(Ba Ca Sn)TiO3 - (1-x) Ba(Zr Ti)O3 perovskite solid solution system.

(EAM-P007-2018) Influence of KBT on the structure and ferroelectric properties of BCZT ceramicsM. N. Al-Aaraji*1

1. University of Manchester, School of Materials, United Kingdom

Barium titanate ceramics modified by calcium and zirconium dopants, denoted BCZT, exhibit promising piezoelectric properties with a piezoelectric charge coefficient, d33, in the region of 600 pC/N being reported at room temperature. The need for high sintering temperatures for densification of BCZT is a serious concern, partic-ularly when considering the compatibility with certain substrates for thick film deposition. It has been proposed that the incorpora-tion of bismuth-based perovskite compounds, such as BiFeO3 and Bi(Mg0.5Ti0.5)O3 into BCZT could both increase the temperature-sta-bility of properties and improve the sintering behavior. The aim of the present study was to determine the effects of adding (K0.5Bi0.5)TiO3 (KBT) into BCZT solid solutions having 2 different calcium titanate contents. The effects of increasing KBT content, in the range from 0 to 65 mol%, on phase transition behaviour, densification, microstructure, dielectric, ferroelectric and piezoelectric properties of these ceramics were systematically investigated. Subsequently, further investigations were conducted to eliminate second phase formation and enhance the ferroelectric properties through the incorporation of excess bismuth oxide and optimisation of the heat treatment procedures.

(EAM-P008-2018) Ab-Initio Prediction of Novel 2D Group-III Oxides by Evolutionary AlgorithmsH. Lester*1; B. Revard2; M. Ashton1; D. Gluhovic1; R. G. Hennig1

1. University of Florida, Materials Science and Engineering, USA2. Cornell University, USA

Combining an efficient evolutionary algorithm for the search of the energy landscape of two-dimensional (2D) materials with accu-rate density-functional theory (DFT) calculations, we predict new, low-energy 2D materials in the family of group-III oxides, A2O3 with A=B, Al, Ga, and In. For B2O3, we discover a planar 2D struc-ture with a surprisingly low formation energy of about 20 meV/atom relative to bulk B2O3. For Al2O3, we identify a structure consisting of 2 Al and 3 oxygen layers with a formation energy of about 190 meV/atom. These formation energies are comparable to those of exper-imentally synthesized 2D materials indicating that these materials could be grown by techniques such as MBE and CVD. We find that 2D B2O3 and Al2O3 are semiconducting and that 2D Al2O3 is stable in aqueous environments, indicating potential applications in elec-tronic devices and as protective layers.

(EAM-P009-2018) Effects of Dysprosium Oxide on Sintering Behavior and Electrical Conductivity of Samarium Doped CeriaS. L. Reis*1; E. N. Muccillo1

1. Energy and Nuclear Research Institute, Brazil

Solid electrolytes based on rare earth-doped cerium dioxide are of considerable interest for potential application in intermedi-ate-temperature solid oxide fuel cells, IT-SOFC. Nevertheless, some constraints related to their sintering behavior along with improve-ment of the ionic conductivity are still object of investigation. In this work, dysprosium ion was chosen as a second additive/dopant, aiming to obtain a ceramic solid electrolyte with optimized ionic conductivity. Compounds of Sm0.2-xDyxCe0.8O1.9 with 0 % x % 0.2 were prepared by solid-state reaction, and the influence of the addi-tive content on densification and ionic conductivity was analyzed by density, X-ray diffraction and impedance spectroscopy measure-ments. All compositions were found to exhibit cubic fluorite-type structure. The sintered solid electrolytes achieved densities higher than 92% of the theoretical value after sintering at 1500°C/3 h, and higher ionic conductivity than the Sm0.2Ce0.8O1.9 parent electrolyte.


Abstracts

(EAM-P010-2018) Samaria-doped ceria with impregnation of molten lithium/potassium carbonate for application as CO2 separation membranesT. Porfirio1; E. N. Muccillo1; F. Marques2; R. Muccillo*1

1. Energy and Nuclear Research Institute, Brazil2. University of Aveiro, Portugal

Composite membranes for carbon dioxide separation were obtained with vacuum infiltration of an eutectic mixture of potassium and lithium molten carbonates into a samaria-doped ceria (SDC) porous matrix at high temperature. Porous SDC were obtained by thermal removal of LiF sacrificial pore former. Scanning electron microscopy and scanning probe microscopy micrographs allowed for estimating pore volume and molten carbonate percolation through porous SDC. Impedance spectroscopy measurements at temperatures below and above the melting temperature of the carbonates show the contributions of oxide and carbonate ions to the total electrical conductivity of the ceramic membranes, which is dependent on the pore volume.

(EAM-P011-2018) Freeze casting of LAGP electrolyte for textured 3D all-solid-state lithium-ion battery multifunctional compositesW. Huddleston*1; F. Dynys2; A. Sehirlioglu1

1. Case Western Reserve University, Department of Materials Science and Engineering, USA

2. NASA Glenn Research Center, USA

In this study, all-solid-state structural lithium-ion batteries, a type of load bearing electrochemical energy storage that provides systems-level weight savings, is being pursued for the reali-zation of inherently safe next generation hybrid-electric and all-electric green aerospace propulsion systems. Currently investigated all-solid-state batteries do not meet the requirements for specific power and mechanical stability. To address these issues, freeze casting of lithium aluminum germanium phosphate (LAGP) elec-trolyte material has been explored for the creation of a textured 3D electrolyte scaffold with large interfacial surface area for high power discharge and hierarchical porosity for accommodation of active material volume changes during electrochemical cycling. We report the effects of freeze casting processing parameters on the microstruc-tural development and mechanical performance of the scaffolds, characterized through scanning electron microscopy and ring-on-ring mechanical testing. Slurry composition and casting parameters such as solids loading, casting speed, tape angle, and temperature gradients have been modified to determine the impact on density, lamellar morphology, and final load bearing performance.

(EAM-P012-2018) Shape and size dependent phase transformations and field-induced behavior in ferroelectric nanoparticlesK. Pitike*1; J. Mangeri2; H. Whitelock2; T. Patel1; P. Dyer1; O. Heinonen3; P. Alpay1; S. Nakhmanson1

1. University of Connecticut, Materials Science and Engineering, USA2. University of Connecticut, Department of Physics, USA3. Argonne National Lab, Material Science Division, USA

Composite materials made up of ferroelectric nanoparticles dispersed in a dielectric matrix are being actively investigated for a variety of novel electronic and energy harvesting applications. However, the dependence of their functional properties on shapes, sizes, orientation and mutual arrangement of ferroelectric parti-cles is currently not fully understood. We utilize a time-dependent Ginzburg-Landau approach combined with coupled-physics finite-element-method based simulations to study the effects of shape, size and mutual arrangement of ferroelectric nanoparti-cles on their polarization topology, both equilibrium and under applied electric and elastic fields. Perovskite PbTiO3 and BaTiO3 are employed as generic ferroelectric materials, while air and SrTiO3, are used as the dielectric matrix. Particle shapes considered involve

members of the superellipsoidal series, i.e., octahedron, sphere, cube and intermediate shapes. We observe a rich variety of polarization textures and interesting transitions between them, as the particle shape and size are being changed. We also find that the composite system response to an applied field, i.e., the shape of its P vs E loop, is tunable by controlling the particle size and orientation. In partic-ular, multistage switching is possible in particles with vortex-like polarization textures, which may be useful for memory applications.

(EAM-P013-2018) Mesoscale modeling of stress induced band-gap attenuation in ZnO NanowiresMesoscale modeling of stress induced band-gap attenuation in ZnO NanowiresL. Kuna*1; J. Mangeri1; P. Gao2; S. Nakhmanson2

1. University of Connecticut, Physics, USA2. University of Connecticut, Institute of Materials Science, USA

Semiconducting zinc oxide (ZnO) is a highly attractive material for nanoscale applications, since it can be easily shaped into a wide variety of different shapes, including nanopillars and nanowires. Here, we have utilized a mesoscale finite-element based modeling approach to study stress induced band-gap changes in monolithic ZnO nanowires with diameters ranging from 100 to 800 nanometers. Obtaining good agreement with experimental results for the mono-lithic wires, we have also investigated core/shell Zn/ZnO nanowire geometries. Size, shape, morphology, core/shell volume ratio and core protrusion beyond the shell were optimized for maximum band-gap downshifts. For the core/shell nanowire arrangements we predict downshifts in excess of 0.25 eV, as compared to the 0.1 eV maximum downshift measured in monolithic wires, which, in combination with other band-gap manipulation techniques, can greatly expand the utility of such nanostructures for optoelectronic applications.

(EAM-P014-2018) Dielectric Properties of Ferroelectric Materials on Aerospace AlloysT. Patel*1; P. Alpay1; R. Hebert1


The current trend of additive manufacturing aerospace components made from high-temperature alloys has led to the consideration of integrated functionality such as sensors and actuators. The combina-tion of ferroelectric oxides and aerospace alloys to be manufactured in a single process step provokes interest over the compatibility of such materials with its different physical parameters. In this theoret-ical work, the effects of coefficients of thermal expansion mismatch on materials properties are examined for PZT 20/80 thin films on four conventional, aerospace alloys: Inconel 718, Ti-6Al-4V, Al6061, and stainless steel 17-4 PH. A non-linear thermodynamic model is employed to calculate dielectric, pyroelectric and piezoelectric properties as a function of growth temperature for these systems. It is found that there are shifts in the ferroelectric phase transition to higher temperatures due to compressive thermal strains. As a result, the dielectric constants of PZT 20/80 on Ti-6Al-4V, stain-less steel 17-4 PH and Inconel 718 with a growth temperature (TG) of 700 °C all surpass that of bulk PZT 20/80. The former two also have higher pyroelectric and piezoelectric coefficients than bulk, which indicate its suitability for potential applications. PZT 20/80 on Ti-6Al-4V deposited at TG=700 °C displays the largest response of p=0.0412 µC cm-2 °C-1 and d33=97.439 pC/N at room temperature.

(EAM-P015-2018) Effect of Gd2O3 additives on the electrical properties of ZnO varistor at different temperaturesF. H. Al-Hamed*1

1. Najran University, Saudi Arabia

The influence of Gd2O3 (0, 0.2, 0.5, 1, 1.5) mol% additives on electrical properties of ZnO – Pr6O11 – Co3O4 – Cr2O3 – Gd2O3 (ZPCCG) – based varistors were studied. Samples were prepared by using the standard ceramic technique (traditional thermal chemistry method). The grain size of prepared samples was obtained by SEM.


Abstracts

The DC measurements (nonlinear properties, capacitance – voltage characteristics) and dielectric properties at different temperatures (25, 50, 75, 100, 125, and 150oC) and in the frequency range 20Hz to 3MHz were determined. The values of α and EB decreased with increasing temperature. The potential barrier height φB increased with increasing temperature. The Relation between Conductivity and Temperature. It was observed that the conductivity decreased with decreasing temperature.

(EAM-P016-2018) Evaluation of coloration behavior with york-shell structured core-shell a-Fe2O3 nanorodR. Yu1; G. An1; Y. Kim*1

1. Korea Institute of Ceramic Engineering and Technology (KICET), Republic of Korea

In this study, hollow type α-Fe2O3@SiO2 nanoparticles were fabricated by treatment of SiO2 shell with mild basic solution. The α-Fe2O3 takes center stage for red pigment due to eco-friend-liness and low cost. Hollow silica have been of long-term interest due to their potential uses for controlled drug release, coatings, and micro reservoirs containing catalysts for confined reactions. The spindle shaped α-Fe2O3 nanoparticles were initially prepared as core materials and subsequently coated with silica using sol-gel method. The hollow structure core-shell particles were produced by dissloution of SiO2 layer with NH4OH. The redness value of the etched samples (a* = +24.94) was higher than that of the hematite sample (a* = +20.08), these samples had values lower than that of the coated sample (a* = +31.28). The morphology and coloration of each samples were investigated in detail by transmission electron micros-copy (TEM), and CIE Lab color parameter measurements.

(EAM-P018-2018) Finite Element Modelling of Poly(Methyl Methacrylate)/Methyl Ammonium Lead Iodide CompositesC. D. Kennedy*1; J. S. Dean1; D. C. Sinclair1; I. M. Reaney1

1. The University of Sheffield, Material Science and Engineering, United Kingdom

Methyl ammonium lead iodide MALI (CH3NH3PbI3) has a perovskite structure (εr = 60) and may be fabricated at room temperature using a mechano-synthesis route in ethanol. In this study, MALI is used to form MALI/Poly(methyl methacrylate) PMMA composites. Finite element modelling is used to simulate the electrical response of MALI particles dispersed in PMMA. The results are compared to experimentally determined values of permit-tivity as a function of the volume fraction of MALI.

(EAM-P019-2018) Electrical conductivity of ceria electrodes for use in MHD generatorsB. L. Wright*1; M. Johnson1; D. Cann1; K. Kwong2; C. Woodside2

1. Oregon State Univ, School of Mechanical, Industrial, and Manufacturing Engineering, USA

2. U.S. Department of Energy, National Energy Technology Laboratory, USA

Direct power extraction using oxy-fuel combustion and magnetohy-drodynamics (MHD) has the potential to increase a thermal power plant’s efficiency by adding a high temperature energy conversion process to existing power cycles. Within an MHD generator, accel-erated oxy-combustion products are expected to have temperatures of about 2400 to 3000 K. Electrodes at the generator walls are used to extract the power. The development of high temperature elec-trodes is desirable in order to reduce wall heat losses, among other considerations. In this work, ceria-based ceramic electrodes were developed for use as MHD electrodes. Ceramic disks of undoped CeO2 and Y2O3 - and Gd2O3 -doped CeO2 were synthesized using solid state synthesis. The sintered ceramics were analyzed via x-ray diffraction, and the electrical properties were measured via imped-ance spectroscopy and current-voltage measurements. In addition, the electrochemical potential measurements were conducted to determine the role of ionic conductivity in these materials. Overall,

the doped CeO2 ceramics exhibited an increase in conductivity with values approaching 10 S/m at 1500 K, with electronic conductivity dominating in the doped compositions. Corrosion tests also indi-cated these materials are relatively inert in the presence of K2CO3 up to 1500°C. Overall, these tests suggest that ceria-based ceramic elec-trodes show promise for use in MHD generators.

(EAM-P020-2018) Electric-Field Induced Strains in (Bi0.5Na0.5)TiO3-(Bi0.5K0.5)TiO3-Based PiezoceramicsS. K. Gupta*1; M. Hilliker1; D. Cann1


Piezoelectric materials based on lead zirconate titanate (PZT) have long been researched and commercialized in applications involving sensors, actuators, and transducers. The high polarizability and electronic structure of lead give PZT its impressive piezoelec-tric properties. In recent years, however, lead-free piezoceramics have seen increasing focus due to the high toxicity of lead. Of the common lead-free alternatives, (Bi0.5Na0.5)TiO3-(Bi0.5K0.5)TiO3 (BNT-BKT) based piezoelectric solid solutions exhibit comparable properties to PZT: d33 = 126 pC/N, d33* = 214 pm/V, k33 = 0.56, and Td = 206 °C. The addition of a ternary compound to BNT-BKT has been shown to lead to higher effective piezoelectric constants with values of d33* surpassing 500 pm/V. This has been demonstrated with a large number of ternary compounds including (K,Na)NbO3, SrTiO3, and a variety of BiMeO3 compounds. The mechanism behind these high strains is tied to an electric-field induced phase transformation involving a non-polar pseudo-cubic phase transi-tioning into a polar tetragonal or rhombohedral phase, accompanied by a large longitudinal strain. This poster will summarize recent work on ternary compounds in this system and explore the relation-ship between the d33* and chemical and structural characteristics in the BNT-BKT-ABO3 solid solutions.

(EAM-P021-2018) When do parallel pathways influence the brick work layer model in electroceramics and how should we analyse their impedance spectra?J. P. Heath*1; J. S. Dean1; J. Harding1; D. C. Sinclair1

1. University of Sheffield, Material Science and Engineering, United Kingdom

Impedance spectroscopy is a useful technique to interrogate elec-troceramics over a spectrum of frequencies potentially revealing more information about core-shell and grain boundary effects than can be obtained from DC or fixed frequency measurements. This makes impedance spectroscopy a sensitive and attractive character-isation technique. A disadvantage, however, is how best to analyse the data. Firstly, there is the choice of an equivalent circuit to model the data. Traditionally, a dual RC circuit (bulk and grain boundary components connected in series) has been popular for conven-tional electroceramics with its applicability best suited to ceramics with thin resistive grain boundaries (brick work layer model). This approach neglects the grain boundaries in parallel with the bulk ceramic. However, with increasing use of core-shell microstructures and nano-grained ceramics is this approach valid when the bulk is of similar thickness to the grain boundary? Previous models have attempted to use a parallel brick layer model to fit nano-grained ceramics. Here we present finite element simulations of core-shell microstructures with the aim of demonstrating preferred fitting procedures. An overview of which impedance formalism (or combi-nation of formalisms) works best for core-shell microstructures with a range of shell properties will also be given.


Abstracts

(EAM-P022-2018) Comparative study of macroscopic and nanoscale polarization switching in large area PLD grown PZT thin filmsM. Rath*1

1. IIT Madras, Physics, India

By optimizing laser rastering conditions and controlling PbO evap-oration, we have grown high quality large area PbZrxTi1-xO3 (PZT) thin films using off-axis pulsed laser deposition (PLD) method. The realization of high quality PZT thin films over a large area with uniform polarization is a challenging problem because of the formation of non-ferroelectric or pyrochlore like PbTi3O7 phases at higher temperature. The polycrystalline nature of the sample with RMS surface roughness around 2.6 nm was observed in our result. We demonstrate the existence of stoichiometry ferroelectric PZT thin films over a large area which was confirmed by recording both in macroscale and nanoscale level of polarization mapping with remnant polarization (2Pr) of 62 µC/cm2 and observation of only 1800 ferroelectric domain switching respectively. The achievement of high quality large area PZT thin films with uniform polarization is of immense importance for PZT based devices such as under-water SONAR devices and in power harvesting.

(EAM-P023-2018) Field- and temperature-driven transitions in graphitic samples as signatures of superconducting fluctuationsN. Gheorghiu*2; C. Ebbing3; T. J. Haugan1

1. Air Force Research Lab, AFRL/RQQM, USA2. UES, Inc., USA3. University of Dayton Research Institute, USA

Nature is a wealth of phase transitions like the ubiquitous ice-wa-ter-vapor, ferromagnetic, ferroelectric, martensitic, nematic to smectic liquid crystal, or normal to superconducting phase. An order parameter characteristic to the physical system undergoes changes about the transition point. In this work, graphitic samples are investigated via PPMS magnetization and magneto-transport measurements with temperatures in the range 1.9 K to 300 K and magnetic fields up to 9 T. Metal-insulating and reentrant insulat-ing-metal transitions, known to be of quantum nature, are observed in the temperature-dependent resistivity. From magneto-transport and magnetizations measurements we have found either tempera-ture-, electric field- or magnetic field-induced phase transitions. Features that resemble those characteristic to high-temperature superconductors might be due to the interplay between excitonic, magnetic, and superconducting fluctuations. Acknowledgements: The Air Force Office of Scientific Research (AFOSR), The Aerospace Systems Directorate (AFRL/RQ), and United Energy Systems (UES, Inc.)

(EAM-P024-2018) Status of Cryogenic/Superconducting Drivetrain Technologies for Electric Propulsion of AircraftT. J. Haugan*1; G. Panasyuk2

1. U.S. Air Force Research Laboratory, USA2. UES Inc, U.S. Air Force Research Laboratory, USA

Hybrid-electric-vehicle (HEV) or electric-vehicle (EV) propul-sion is well understood from the automotive industry, and achieves very significant increases of energy efficiencies of 2-3x from the use of non-combustion technologies and ‘smart’ energy manage-ment including brake regeneration. The use of battery-electric and hybrid-electric propulsion for aircraft has increasingly been realized in the last 5 years, and has been successfully implemented in 2 and 4 passenger aircraft. This paper will summarize recent progress in this field for aircraft, and present case studies of how cryogenic/superconducting electric power systems can positively impact hybrid-electric or all-electric power systems and capabilities, for different size and power level aircraft. Cryogenic drivetrain and components studied include generators and motors, power trans-mission cables, power storage devices including Li-batteries and

superconducting magnetic energy storage (SMES), power elec-tronics including inverters, and cryocooling technologies. Properties of cryogenic systems and components will be presented, including technical readiness level and scaling of power densities for varying power level, and these properties will be compared to Cu-wire based systems.

(EAM-P025-2018) Comparison Study of the Flux Pinning Enhancement of YBa2Cu3O7-δ Superconductor with BaHfO3 and Y2O3 Single and Mixed Phase AdditionsM. Sebastian*2; C. Ebbing2; T. Bullard6; W. Zhang4; J. Huang4; H. Wang4; B. Gautum5; C. Shihong5; J. Wu5; T. J. Haugan1

1. Air Force Research Lab, AFRL/RQQM, USA2. UDRI, USA4. Purdue University, School of Materials Engineering, USA5. University of Kansas, Dept. of Physics & Astronomy, USA6. UES, USA

Adding nanophase defects to YBa2Cu3O7-δ (YBCO) superconductor thin films is well-known to enhance flux pinning, resulting in an increase in current density (Jc). While many previous studies focused on single phase additions, the addition of several phases simultane-ously shows promise in improving current density by combining different pinning mechanisms. This paper compares the effect of the addition of two insulating, nonreactive phases of barium hafnium oxide (BHO) and yttrium oxide Y2O3, both as a single addition of BHO and as a double addition in conjunction with Y2O3. Processing parameters vary the target composition volume percent of BHO from 2-6 vol. % for the single doped YBCO targets while main-taining 3 vol. % Y2O3 for the double doped YBCO targets. Pulsed laser deposition produced thin films on LaAlO3 (LAO) and SrTiO3 (STO) substrates at various deposition temperatures. Comparison of strong and weak flux pinning mechanisms, current densities, crit-ical temperatures, and microstructures of the resulting films will be presented.

(EAM-P026-2018) YBa2Cu3O7 thin films with large, congruent, columnar Y2BaCuO5 pinning centers: Magnetization creep and decayC. Myers*1; M. Sebastian2; M. A. Susner2; M. D. Sumption1; T. J. Haugan2

1. Ohio State University, Materials Science and Engineering, USA2. Air Force Research Lab, Aerospace Systems Directorate, USA

Maximizing critical current density (Jc) and minimizing flux creep in high temperature superconductors (HTS) is critical for their inclu-sion in accelerator magnets where both high magnitude magnetic fields and high magnetic field stability are required. However, whereas critical current density can be enhanced by the addition of many shallow pinning centers, or the addition of fewer deeper pins, flux creep is better managed by the addition of deep pins. Pulsed laser deposition (PLD) was used to synthesize YBCO samples with different types of pinning centers. Uniquely structured YBa2Cu3O7 samples with large congruent nanorods of Y2BaCuO5 were fabri-cated with volume fractions of 0, 5, 10, and 15%. XRD and TEM characterization was performed. Magnetic Jc(B,T,q) properties were determined. Additionally, the magnetic relaxation of the samples was measured at fields from 0-8 T and at temperatures of 4.2 to 77 K. The results of these measurements were used to generate U(J) vs J curves for each sample; fits were attempted to extract an intrinsic pinning potential (U0).


Abstracts

(EAM-P027-2018) Calorimetric Measurements of YBCO Conductors and Cables at High dB/dt in a Stator Machine EnvironmentT. J. Haugan*1; J. P. Murphy2; M. D. Sumption3; E. W. Collings3; T. Bullard5

1. U.S. Air Force Research Laboratory, AFRL/RQQM, USA2. University of Dayton Research Inc, U.S. AFRL, USA3. The Ohio State University, USA5. UES Inc, U.S Air Force Research Laboratory, USA

A new apparatus for measurement of AC loss in superconductors at high dB/dt has been developed, and recently tested and calibrated for operation. The test device has a spinning rotor consisting of permanent magnets arranged in a Halbach array; which exposes samples in a stator position with a peak radial field of 0.57 T, and with high rotation speeds up to 3600 rpm achieves a radial dB/dt is 543 T/s and tangential dB/dt is 249 T/s. Loss is measured by calorimetry using nitrogen boiloff from a double wall calorimeter, and the system was calibrated using power from a known resistor. For calibration, Cu-tape and YBCO-tape losses were measured and compared to results of a solenoidal magnet AC loss system measure-ment of the same samples but limited to a field of amplitude 0.1 T and a dB/dt of 100 T/s. Herein the use of this system for measuring AC losses of a variety of YBCO coated conductors and cables will be performed, and results will be compared to measurements with a solenoid magnet system and theory. Coated conductors are provided by several manufacturers with different architectures including fila-mented, varying width, and different quench protection metal layers with varying thickness. Also AC losses will be reported on several types of cable structures, including stacked tapes and conductor-on-round-core (CORC) structures.

(EAM-P028-2018) Quasistatic Phononic Energy Transport between Nanoparticles Mediated by a MoleculeG. Y. Panasyuk*2; K. L. Yerkes3; T. J. Haugan1

1. Air Force Research Lab, AFRL/RQQM, USA2. UES Inc., USA3. Air Force Research Lab, AFRL/RQQI, USA

We consider phononic energy transport between nanoparti-cles mediated by a molecule. The nanoparticles are considered as thermal reservoirs described by ensembles of finite numbers of harmonic oscillators within the Drude-Ullersma model having, in general, the time scale t ~ 1/Δ1,2 is investigated using the gener-alized quantum Langevin equation. The equations describing the dynamics of the averaged eigenmode energies are derived and solved, and the resulting expression for the energy current between the unequal mode spacings Δ1 and Δ2, which amount to different numbers of atoms in the nanoparticles. The quasistatic energy transport between the nanoparticles on nanoparticles is obtained and explored. Unlike the case when the thermodynamic limit is assumed resulting in time-independent energy current, finite-size effects result in temporal behavior of the energy current that evinces reversibility features combined with decay and possesses peculiari-ties at time moments t = 2πn/Δ1 + 2πn/Δ2 for non-negative integers n and m. When Δ1,2→ 0, an expression for the heat current obtained previously under assumption of the thermodynamic limit is repro-duced. The energy current between two platinum nanoparticles mediated by a carbon oxide molecule is considered as an application of the developed model.

(EAM-P029-2018) Designing Electromechanical Properties of (Na1/2Bix)TiO3-Based Ferroelectrics Through A-Site Non-StoichiometryT. Frömling*1; S. Steiner1; A. Ayrikian2; M. Dürrschnabel1; M. Leopoldo1; H. Kleebe1; H. Hutter3; K. G. Webber2; M. Acosta4

1. Technische Universität Darmstadt, Materials Science, Germany2. Friedrich-Alexander-Universität Erlangen-Nürnberg, Materials Science

and Engineering, Germany3. Technische Universität Wien, Institute of Chemical Technologies and

Analytics, Austria4. University of Cambridge, Materials Science and Metallurgy,

United Kingdom

Defects influence the properties of ferroelectrics to a great extent. So far, limited knowledge exists on the impact of cation vacancies on these materials, especially on (Na1/2Bi1/2)TiO3 (NBT)-based material. Here, we report on the drastic effect of A-site non-stoichiometry on the cation diffusion and functional properties exemplarily for the (Na1/2Bi1/2)TiO3-SrTiO3 (NBT-ST) solid solution. Experiments on NBT/ST bilayers and NBT-ST with Bi non-stoichiometry reveal that Sr2+-diffusion is enhanced up to nine orders of magnitude in the Bi-excess material as compared to the Bi-deficient material. This in turn leads suppression of a core-shell microstructure and 6 times larger grain size in the Bi-deficient material. The changes in microstructure also result in 38 % higher strain and one order of magnitude higher polarization in the Bi-excess material. Thus, the work sheds light on the rich opportunities that A-site stoichiometry offers to tailor NBT-based materials cation transport, microstruc-ture, and electromechanical properties.

(EAM-P030-2018) Fractal Hull of Grains Cluster Boundary of Ceramics and Micro ImpedancesV. Mitic*1; V. Paunovic2; L. Kocic2

1. Serbian Academy of Sciences, Institute of Technical Sciences, Serbia2. Faculty of Electronic Engineering, University of Nis, Serbia

The capacity component in micro impedances is an important prop-erty of electronics ceramics. Intergranular structure and dielectric properties of a grains cluster can be advanced simulated using fractal hull (FH) of boundary configuration. In the porous powder mate-rial, two aspects of cluster fractality FH have been noticed - the space of holes (pores) as a negative space and the positive space made by collection of grains. Several types of the FH are proposed. The average one, local, weak limited etc. For classical hull, it is possible to have six intergranular connection types. For the FH contents, with the corrected degree of the scale depend diameter, the new ways exist for grain clusters contact between maximums and minimums of the grain boundaries. This approach directly affects description of the surface area energy reduction and concept of working tempera-ture of BaTiO3-ceramics, i.e. its dielectric and conductive properties. Since the REE (REM) additives may substantially increase fractality of ceramics clusters, the proposed method is useful to consider the issue of super capacity.

(EAM-P031-2018) Lead Free Thick Films Produced via Aerosol DepositionE. Gorzkowski*1; E. Patterson3; S. D. Johnson1; D. Park2

1. Naval Research Laboratory, USA2. Korea Institute of Materials Science, Republic of Korea3. ASEE, USA

Aerosol deposition (AD) is a thick-film deposition process that can produce layers up to several hundred micrometers thick with densi-ties greater than 95% of the bulk. The primary advantage of AD is that the deposition takes place entirely at ambient temperature; thereby enabling film growth in material systems with disparate melting temperatures. The bonding and densification of the film and film/substrate interface are thought to be facilitated by local temperature rise, high pressure, and chemical bonding during deposition, which leads to a dense nano-grained microstructure.


Abstracts

In this talk we present results on the deposition of dielectric and ferroelectric materials deposited by aerosol deposition including the effect of processing parameters on the resultant material properties.

(EAM-P032-2018) Cold Sintering Process of Magnetodielectrics for Radio Frequency (RF) ApplicationsS. El-Faouri*1; I. M. Reaney1


M-type hexaferrites, e.g. BaFe12O19, have attracted a lot of atten-tion because of their excellent magnetic properties and potential application in various fields [1]. They are utilized throughout the electroceramic industry not only in magnetic storage systems [2,3,4] but also as RF substrates in the fabrication of filters and antennas. The cold sintering processing (CSP) is a novel technique developed recently to achieve dense ceramics at extremely low temperatures (<180 °C) across a variety of ceramics, ceramic/ceramics and ceramic/metal and polymer/ceramic composites [5]. The process utilises a small volume fraction of aqueous-based solutions as tran-sient solvents to aid densification by a nonequilibrium mediated dissolution–precipitation process [6]. Magnetodielectric compos-ites have been fabricated using CSP at 120°C from BaFe12O19 and Li2MoO4 end members. The microstructure, structure and proper-ties of these composites have been studied with a view to developing substrates with bespoke permeability and permittivity for RF applications.

(EAM-P033-2018) Investigation of the Sintering and Microstructural Evolution of CuO-doped Ternary Relaxor-PbTiO3 CeramicsB. H. Watson*1; M. J. Brova1; Y. Chang1; E. R. Kupp1; J. Wu1; M. A. Fanton1; R. J. Meyer1; G. L. Messing1

1. Pennsylvania State University, Materials Science & Engineering, USA

The t e rnary Pb( In 1/2Nb 1/2)O 3-Pb(Mg 1/3Nb 2/3)O 3-PbTiO 3 (PIN-PMN-PT) relaxor ferroelectric system has recently attracted considerable attention because of its broader temperature usage range, higher coercive field and comparable piezoelectric properties to binary PMN-PT. Within the development of these ternary relaxor ferroelectric ceramics, doping engineering has emerged as a strategic approach for tuning electrical properties, phase transition tempera-tures, and sintering mechanics in this system. CuO, for example, promotes sintering and densification in PbTiO3-based ceramics at lower temperatures by forming a liquid phase eutectic with PbO, however, the influence of the dopant on the kinetics of phase forma-tion and sintering in ternary relaxor ferroelectrics has seldom been investigated. In this work, the effects of CuO-doping on the phase formation of PIN-PMN-PT ceramics were observed using x-ray diffraction analysis on isothermally heated powders, and the kinetics of phase formation were then modeled as a function of time and temperature. The influence of the dopant on the sintering mechanics was also investigated using phase pure PIN-PMN-PT powder, as well as a reactive approach, to obtain a better understanding of the microstructural development.

(EAM-P034-2018) Giant Energy Storage Performances and Wide Temperature Range of Lead-free Capacitors with Different Orientation on LSMO buffersZ. Sun*1; M. Liu1

1. Xi’an Jiaotong University, School of Microelectronics, China

Mechanism of crystallographic orientations and LSMO buffer thick-ness on the dielectric and energy storage properties of lead-free epitaxial BCT/BZT multilayers (numeric periodicity=4) fabricated on Nb doped SrTiO3 (NSTO) substrates by using radio frequency magnetron sputtering system have been detailedly investigated. The strong orientation dependence of ferroelectric properties of the multilayers is attributed to the relative alignment of crystallites and spontaneous polarization vector, while the decreasing elec-trical breakdown strength of increasing buffer thickness can be

explained by the inferior crystal quality, which is observed by the rocking curves. A high energy storage density of 37.6 J/cm3 with h equals 77.6% was obtained on the (001)-orientated multilayer with 20 nm LSMO buffer, and these quite good energy storage perfor-mances sustain even at as high as 200 oC. All these results revealed an important way for tuning the energy storage performances by LSMO buffer, suggesting the potential application of lead-free electronics in lead-free energy storage industries.

(EAM-P035-2018) Processing and properties of textured polycrystalline LiTaO3 ceramicsJ. Ivy*1; G. L. Brennecka1

1. Colorado School of Mines, USA

Lithium tantalate (LiTaO3) is a ferroelectric ceramic with a highly anisotropic coefficient of thermal expansion, approximately a 4x difference between the z and x or y directions, which makes creating polycrystalline specimens very challenging. Here, textured polycrys-talline LiTaO3 ceramics have been produced via a templated grain growth tape casting method. A templated microstructure is achieved through the use of seed crystals which are made by controlled spall-ation of the surface layer of z-cut LiTaO3 single crystals and are then dispersed in a ceramic slurry and oriented with their crystallographic c-axis parallel to the thickness direction of the tape. Dielectric and ferroelectric properties are discussed and compared to conventional single crystal specimens. This work is supported by the National Science Foundation (DMR-1555015).

(EAM-P036-2018) Interfacial Charge Polarization in a Nano-Domained Polymer-Derived Amorphous SiAlCN CeramicH. Li*1; L. An1

1. University of Central Florida, Materials Science and Engineering, USA

A nano-domained polymer-derived SiAlCN ceramic was synthesized with its microstructure and frequency-/temperature-dependent dielectric properties and impedance behaviors characterized. A major change in its dielectric constant is observed, most probably caused by a strong interfacial polarization process. The interfacial polarization induced dielectric loss peaks were found to move to higher frequencies with either increasing pyrolysis temperature or with rising testing temperature. The peak-shifting effect of the pyrol-ysis temperature is mainly attributed to the dominating increase in the conductivity of the nano-sized free carbon phase, causing short-ened relaxation times. Testing temperature, in a similar manner, accounts for the rise in the conductivity of the free carbon phase thus the decreased relaxation times, with the relaxation process follows a band-tail hopping mechanism within the nano free carbon phase. Impedance analysis reveals two relaxation processes stem from the bi-phasic nature of the material, and also confirms the presence of accumulated space charge. Electric modulus, dielectric loss and impedance results support the hopping type of conduction mecha-nism between localized states due to interfacial polarization.

(EAM-P037-2018) Temperature Stable Dielectrics Based on BaTiO3-Bi(Zn1/2Ti1/2)O3-La(Zn1/2Ti1/2)O3 -Pb(Ni1/3Nb2/3)O3

Z. Colton*1; D. Cann1


High energy density ceramic capacitors with temperature stable permittivity across -150°C to 300°C are desired for a wide variety of electronic devices. The goal of this work is to create a perovskite material that has a high level of B site cation disorder to take advan-tage of a relaxor dielectric mechanism that helps realize temperature stable dielectric properties. Ceramic solid solutions were synthe-sized from oxide and carbonate precursors and calcined in air at temperatures ranging from 900 to 1050°C and sintered in air at temperatures ranging from 1050 to 1200°C. Initial results focused on the BaTiO3-Bi(Zn1/2Ti1/2)O3- La(Mg1/2Ti1/2)O3 ternary system showed a minimal temperature dependence with a temperature


Abstracts

coefficient of permittivity (TCe) as low as -136.5 ppm/°C. However, the reduced permittivity values observed in these compounds motivated the inclusion of Pb(Ni1/3Nb2/3)O3 to increase the permit-tivity while hopefully maintaining a low Tmax. The phase equilibria and dielectric properties of compositions based on the compound BaTiO3-Bi(Zn1/2Ti1/2)O3 along with additives La(Zn1/2Ti1/2)O3 and Pb(Ni1/3Nb2/3)O3 were investigated by X-ray diffraction and dielectric measurements. Results of this quaternary system show a sufficient maximum permittivity but a large TCe=1417 ppm/°C. Future work involves optimizing compositional end members that enable the TCe to approach zero.

(EAM-P038-2018) Investigation of the Structural Changes of HfO2 Powders through Doping with Gd and SrJ. Brodie*1; B. S. Johnson1; J. L. Jones1


Due to the recent discovery of ferroelectricity in HfO2 thin films, HfO2 has become an ideal candidate for use in ferroelectric memory devices. It is known that HfO2 is monoclinic and non-ferroelec-tric at room temperature. However, a polar orthorhombic phase is typically observed in ferroelectric thin films. Since high-quality refinements of crystal structures from X-ray diffraction (XRD) data of films is challenging, powders are more suitable for fundamental crystallographic studies. The use of HfO2 powders will enable us to gain a better understanding of the doped HfO2 materials and better inform thin film work. The purpose of this study was to determine the effects of doping and calcination temperature on HfO2 powders using XRD to determine the effect on the crystallographic structure of HfO2. HfO2 was doped with 1, 5, and 9 at.% Gd and 1, 5, and 5 at.% Sr using conventional solid state synthesis. The powders were calcined at 1100, 1300, and 1500°C. A lab X-ray diffractometer was used to measure diffraction patterns. The Rietveld refinement method using GSAS-II was used to analyze the diffraction data to obtain phase fractions, occupancies, and changes in lattice param-eters. Results yielded that a monoclinic and cubic mixed phase formed at every calcination temperature for both dopants, which is consistent with phase diagrams.

Thursday, January 18, 2018

Plenary Session IIRoom: Orange DSession Chair: Brady Gibbons, Oregon State University

8:40 AM(EAM-PLEN- 002-2018) New Materials Paradigm In Oxide Epitaxial Nanocomposite Thin Films and The Realisation of Enhanced FunctionalitiesJ. MacManus-Driscoll*1

1. University of Cambridge, Dept. of Materials Science, United Kingdom

Since the discovery of high temperature superconductivity in perovskite oxides in 1986, the unearthing of a huge range of physical phenomena in transition metal oxides (TMOs) has been nothing short of remarkable, e.g. new magnetics, ferroelectrics, multiferroics, semiconductors, transparent conductors, calorics, plasmonics, cata-lysts, ionic conductors. However, for a variety of reasons ranging from lack of perfection to complexity of processing, to the func-tional effect being too weak, there are few applications of complex oxide films today. This talk will discuss new insight into overcoming these challenges by using epitaxial nanocomposite films. Examples of our recent work on unprecedented functional property enhance-ments in ferroelectrics, ferromagnetics, magnetoelectrics and ionics will be given.


Processing to Control MicrostructureRoom: Nautilus BSession Chair: Scott Misture, Alfred University

10:00 AM(EAM-BASIC-S5-014-2018) Electri-field induced rapid sintering and welding of ceramics (Invited)L. An*1

1. University of Central Florida, USA

It is recently reported that at the presence of electric field, the ceramics can be densified in time as short as a few seconds and at furnace temperature a few hundred degrees lower than conventional sintering temperature. This phenomenon implicates that electric field can trick rapid mass transport. While it was demonstrated for many different ceramic systems, the mechanism underlying the phenomenon has not been fully understood. In this talk, the phenomenon is studied by monitoring the change in conductivity of ceramics during sintering. A basic model is proposed to account the phenomenon. In addition, we will also present our results on electric-field induced rapid welding of ceramics-to-ceramics and ceramics-to-metals.

10:30 AM(EAM-BASIC-S5-015-2018) Characterization and Microscopy of Yttrium-doped Barium Zirconate with Nickel Additions for Catalysis ApplicationsD. Jennings*1; M. Knight1; I. Reimanis1

1. Colorado School of Mines, Materials and Metallurgical Engineering, USA

Steam methane reforming (SMR) is the most common industrial technique for hydrogen production. Typically, hydrogen is produced by flowing steam and methane over fine nickel metal particles supported on an inert ceramic substrate. Recently it has been shown that an active ceramic support, such as yttrium-doped barium zirconate (BZY), may aid in anti-coking and anti-fouling, both of which degrade catalytic performance. The present study examines how BZY-Ni microstructures evolve under SMR environments. BZY powders with low levels of Ni (less than 10 atomic %) are made via a chemical synthesis route. The powders are exposed to reducing conditions, and electron microscopy is used to examine role of surfaces and interfaces in the microstructure evolution.

10:45 AM(EAM-BASIC-S5-016-2018) Electric Field Effects on Crystallization and Microstructure Evolution in BaTiO3 (Invited)E. C. Dickey*1


In the rapidly growing area of electric-field processing of ceramics, it has often been difficult to distinguish the effects of electric fields from electric current on microstructure evolution. This work attempts to isolate the effects of electric fields on the crystalliza-tion and subsequent microstructure development of BaTiO3 thin films. Initially amorphous BaTiO3 films are annealed at tempera-tures between 400°C and 900°C with average DC electric fields ranging from 0V/cm to 800 V/cm. Both closed-circuit and open- circuit conditions are studied to determine the importance of current density on the microstructure development. A variety of electron microscopy and x-ray diffraction techniques are used to investigate the crystallinity, texture and grain size of the annealed


Abstracts

films, and dielectric properties are compared. We find that even moderate field values have a measureable influence on the phase stability and microstructure, indicating that direct electric fields may be utilized as an additional processing parameter.

11:15 AM(EAM-BASIC-S5-017-2018) Epitaxial and Atomically-Thin Metal Films on Graphene: Unique Properties of a Mophologically Constrained System (Invited)F. M. Alamgir*1

1. Georgia Institute of Technology, School of Materials Science and Technology, USA

We will present our results large-area, fully-wetted, atomically thin metal films can be grown epitaxially on graphene (GR). We will focus particularly on Pt films that are one to several multilayers thick (Pt_ML) epitaxially grown on graphene (Pt_ML/GR). These Pt_ML/GR 2D systems have covalent bonds at the Pt_ML/GR interface and this intimacy between the layers serves to make the GR a ‘chemi-cally transparent’ barrier that allows catalytic chemistry to take place above it, while protecting the Pt below it from loss. We will specif-ically show that graphene does not restrict access of the reactants for the canonical oxygen reduction reaction (ORR) but does block Pt from dissolution or agglomeration. These architectures simul-taneously achieve enhanced catalytic activity and unprecedented stability, retaining full activity for ORR beyond 1000 cycles. Using x-ray photoemission/absorption spectroscopy (XPS/XAS), high resolution TEM, AFM, Raman, and electrochemical methods, we show that Pt/GR hybrid architectures induce a compressive strain on the Pt films, thereby increasing their ORR activity. Our room-tem-perature, fully-wetted synthesis approach, should allow for efficient charge, strain, phonon and photon transfer, between the films and their support, impacting not just the performance of catalysts, but also those of electronic, thermoelectric and optical materials.

11:45 AM(EAM-BASIC-S5-018-2018) Plane-like monocrystalline ABi2Nb2O9 (A=Ca, Sr, Ba) with preferential (00l) facets for enhancement photocatalytic activityY. Zhang*1

1. Sichuan University, Materials Science and Engineering, China

The inorganic materials with layered perovskite structure have been studied widely in the field of photocatalysis. Aurivillius compounds have great potential applications in the field of photocatalysis due to their special layer structures and good capabilities of light response. In this work, the plane-like monocrystalline Aurivillius phase ABi2Nb2O9 (A = Ca, Sr, Ba) powders with preferential growth of (00l) facets were prepared successfully by molten salt method. Bi2O3, CaCO3, SrCO3, BaCO3, and Nb2O5, were mixed according to the chemical ingredient ratio. NaC1-KC1 were added as the molten salt. XRD results shew that the molten salt method contributes to obtaining ABi2Nb2O9 (A=Ca, Sr, Ba) crystal grains with better crys-tallinities and preferential growth of (00l) facets. A lot of crystal boundaries existed in the polycrystalline particles and the diffu-sion of photon-generated carriers was affected severely by the grain boundaries. The oxidation and reduction catalytic sites existed on the different facets of plane-like ABi2Nb2O9 (A = Ca, Sr, Ba). The H2 evolution rates of the plane-like monocrystalline ABi2Nb2O9 (A = Ca, Sr, Ba) increased almost an order of magnitude and the O2 evolution rates also increased obviously.


Defect Physics and ChemistryRoom: Nautilus CSession Chairs: Ming Tang, Rice University; Jeffrey Rickman, Lehigh University

10:00 AM(EAM-JOINT-014-2018) Mn doping in SrTiO3 : A combined DFT and experimental investigation (Invited)E. Cockayne*1; K. F. Garrity1; R. A. Maier1; I. Levin1

1. NIST, USA

The substitution site, valence state, and charge compensation mechanism of dopant transition metal ions control the electronic properties of doped perovskite materials. We use a combination of density functional theory total energy calculations, ab initio molec-ular dynamics, XAFS, and EPR spectra to study the geometry and electronic structure of defects and defect complexes involving Mn substitution in SrTiO3. The defects studied theoretically via supercell calculations include Mn substitution on the A site, Mn substitu-tion on the Ti site (MnTi), Mn substitution on both sites, and MnTi compensated by an oxygen vacancy (VO). The predicted geometries of the defects is used as input to simulate XAFS and EPR spectra, which is then compared with experiment to identify the defects. In particular, the calculations predict various possible charge and spin states in the MnTi +VO defect complex as a function of MnTi -VO distance, information that can be used to identify these defect complexes and determine their charge/spin state experimentally.

10:30 AM(EAM-JOINT-015-2018) Formation of Un-common Valences and Defects in Perovskite Lattice via Revisiting Madelung Energy and Site Potential (Invited)M. Yoshimura*1

1. Tokyo Institute of Technology, Materials and Structures Laboratory, Japan

Many functional oxides would take Perovskite structures (ABO3). The major reason should be understood by the fact that Perovskite lattices would have larger Madelung lattice energies than those of other lattices like NaCl, fluoite, corundum, spinel, garnet., etc. According to the most fundamental ionic model, the total Madelung lattice energy (U) can be expressed by the equation: U = Ne2 ∑ p.q.Φ/2k, where N: Avogadro Number, p: Occurrence of j-ion in the unit cell, q: Valence of j-ion in the unit cell, Φ : Lattice site potential, k: Molecular number in the unit cell, Since the ionization potential [loss] can be compensated by high lattice site potential [gain], high valence ion can be stabilized in a lattice site with high lattice-site potential. For example, Ce4+, Pr4+, and Tb4+ can be stabilized in a Fluorite lattice, and more stabilized in the B site of Perovskite ABO3 lattice. Un-common high-valence ions like Co3+, Ni3+, Fe4+ in the B-sites of the Perovskite ABO3 lattices can be explained similarly. Lattice site potentials have major effects on Valence and Defect in various oxides. Point defects may form in lattice sites having small lattice site potentials. In large potential sites may collapse the pint defects to form edge-sharing (shear) struc-ture(s). It has been clearly demonstrated under summarizing the data.


Abstracts

11:00 AM(EAM-JOINT-016-2018) Energetics of Intrinsic and Extrinsic Defects in Lead-based Hybrid Perovskites from First Principles ComputationsA. Mannodi-Kanakkithodi*1; D. H. Cao2; N. Jeon2; A. Martinson2; M. K. Chan1

1. Argonne National Lab, Center for Nanoscale Materials, USA2. Argonne National Lab, Materials Science Division, USA

Lead halide hybrid perovskite semiconductors have emerged as attractive candidates for photovoltaic applications. Intrinsic point defects and external substituents play an important role in these materials in determining their solar cell efficiencies. Here, we considered MAPbBryCl3-y perovskites (where MA = methylam-monium and y ∈ {0-3}) as parent semiconductors and used first principles computations to study intrinsic defects, namely vacancy, interstitial and anti-site, and extrinsic defects, i.e. defects created by partial substitution of Pb by an external atom. Charge transition energy levels for each defect showed that while low energy intrinsic defects create shallow levels (i.e., close to valence or conduction band), some external substituents create deeper levels in the band gap, which could lead to enhanced solar cell efficiencies owing to sub-gap absorption. Indeed, the latter feature was exploited in the design of Co-substituted MAPBX3 perovskites (X = Br/Cl), where absorption and photoluminescence spectra revealed mid-gap energy states. Further, we determined the equilibrium growth conditions necessary to create stable extrinsic defects that compensate for domi-nant intrinsic defects. Substitution of Pb under these conditions with metals that create deep transition levels is a path towards developing new photovoltaic materials with increased efficiencies.

11:15 AM(EAM-JOINT-017-2018) Multiferroism in Iron-based Oxyfluoride PerovskitesS. T. Hartman*1; S. B. Cho2; A. S. Thind1; R. Mishra2

1. Washington University in St. Louis, Institute of Materials Science and Engineering, USA

2. Washington University in St. Louis, Mechanical Engineering and Materials Science, USA

Hybrid improper ferroelectricity is generated by the combination of cation ordering at the A-site and octahedral tilting, and unlike conventional ferroelectricity, it does not conflict with magnetism. Therefore, it provides a route to achieve multiferroic materials. In this work, we use first-principles calculations to induce ferro-electricity in perovskites with iron in +3 oxidation state to take advantage of its high magnetic-ordering temperature. To maintain charge neutrality in AA’Fe2O6 perovskites, previous attempts to induce ferroelectricity in Fe +3 perovskites have been restricted to using A and A’ with +3 oxidation state, which limits the polarization. We use anion engineering to overcome this restriction and demon-strate polarization as high as 17.5 µC/cm2 in AA’Fe2O5F oxyfluoride perovskites with a combination of A and A’ cations with +2 and +3 oxidation state, respectively. We also show that the presence of strong superexchange interactions in the AA’Fe2O5F oxyfluoride perovskites, leading to a new family of potential room-temperature multiferroics. Design-rules to maximize the polarization as a func-tion of the combination of A and A’ cations will also be discussed.

11:30 AM(EAM-JOINT-018-2018) Multi-Scale Modeling of Sintering of Ceramic Materials with Tailored Structure (Invited)E. A. Olevsky*1

1. San Diego State University, USA

High performance electrochemical systems (e.g. electrodes for solid oxide fuel cells, gas separation membranes and batteries) have microstructural requirements that include high surface area and porosity. These requirements are seemingly contradictory

to the conditions for reliable and stable long-term performance. This apparent contradiction can be addressed by using graded, hierarchical and/or anisotropic porous microstructures. A multi-scale modelling framework for sintering analyses is utilized for the description of the experimentally observed evolution of the pore orientation in textured porous structures. The presentation provides the theoretical framework for understanding the differences between the small and large pore evolution based on the specifics of viscous and diffusional mass transport during sintering processes. A pore size at which transition from intrinsic to extrinsic has been experi-mentally obtained and a hypothesis for this behavior, based on the competition between densification and creep deformation, will be discussed.

12:00 PM(EAM-JOINT-019-2018) Study of Tritium Solubility and Diffusivity in Lithium Aluminate and Lithium Zirconate pelletsH. P. Paudel*1

1. National Energy Technology Lab, Functional Material Designs, USA

Lithium aluminate (LiAlO2) is an insulating material currently being developed by researchers for different applications. It has been used as a suitable substrate for GaN epitaxial growth, coating in Li electrodes, and as an additive in composite Li electrolytes. Most importantly, the high temperature phase (gamma) of LiAlO2, has been used as a tritium breeding blanket for deuterium-tritium (D-T) fusion reactor. It has an excellent irradiation behavior at high temperature, and is better swelling resistant than many other Li rich materials. However, the transport mechanism of tritium through the ceramic pellets and the barrier is hampered by the lack of data such as the diffusivity and solubility of hydrogen isotope. Here we present a first- principle density functional study of diffusivity and solu-bility of tritium in gamma-LiAlO2 and provide an understanding on intestinal and substitutional tritium defects in the considered mate-rial. We consider several possible diffusion pathways for Tritium, Lithium-Tritium, and Oxygen-Tritium diffusion mechanisms. We present our results for at different level of tritium concentration, and provide activation energy profile. We also present similar study in the lithium zirconates (Li2ZrO3).

12:15 PM(EAM-JOINT-020-2018) Exploring the rich defect chemistry of amorphous carbon using a combination of experiments and theoryT. W. Surta*1; Z. Li1; D. Fast1; X. Ji1; P. A. Greaney2; M. Dolgos1

1. Oregon State University, Chemistry, USA2. University of California, Riverside, USA

In this study we correlate experimental electrochemical and diffrac-tion data with computational molecular dynamics (MD) and density functional theory (DFT) models to develop a greater understanding of the role defects play in Na-ion binding within amorphous carbon structures. A simple sucrose derived hard carbon was synthesized, its electrochemical and physical properties characterized, and neutron pair distribution function (PDF) data was collected. Large box (~10,000 atoms) MD models were created using a simulated quench procedure. These models were then subjected to the reverse Monte Carlo (RMC) process to carefully fit the MD models to experimental PDF data. The binding potentials for a variety of the differing struc-tural sites found within the models were then calculated using DFT, allowing for the recreation of the galvanostatic charge discharge data. These recreations were then compared to the experimental electrochemical data, providing further validation to our models and allowing us to determine the structure-property relationships in these amorphous materials. The results of this study reveal that the role of defects is more important than previously understood and informs the community on how to rationally design of new, high performance amorphous carbon anodes.


Abstracts


Emerging Chalcogenide Materials for Electronic, Photonic and Energy ApplicationsRoom: Citrus ASession Chair: Jayakanth Ravichandran, Columbia University

10:00 AM(EAM-ELEC-S1-001-2018) Chalcogenide Perovskites for Photovoltaics (Invited)S. Zhang*1

1. Rensselaer Polytechnic Institute, Physics, USA

Halide perovskites have emerged as a new star in photovoltaics, but their poor stability and the toxicity of Pb have raised serious concerns. Chalcogenide perovskites ABX3 are, on the other hand, friendlier to environment and more stable, and hence could be a good alternative to the halides. First-principles calculation predicted [1] a direct band gap of 1.35 eV, which is ideal for solar cells, for CaZrSe3. Compared to other solar-cell materials, the chalcogenides also have a superior optical absorption. We have experimentally synthesized several chalcongenide perovskites and our optical measurements [2] on these samples validate our theory. In partic-ular, the combined optical absorption and PL measurements suggest that BaZrS3 has a 1.7-eV direct gap, which can be continuously tuned to 2.9 eV by forming oxychalcogenides. Mixing organic-inorganic hybrid perovskites by a split-anion approach offers another alter-native to the halide perovskites. We show [3] that such a splitting opens the door to an unusual combination between indirect band gap for long carrier lifetime and high optical absorption for efficient solar harvesting. [1] Y. Y. Sun, et al., Nano Lett. 15, 581 (2015). [2] S. Pereraa, et al., Nano Energy 22, 129 (2016). [3] Y.-Y. Sun, et al., Nanoscale 8, 6284 (2016).

10:30 AM(EAM-ELEC-S1-002-2018) Kesterite-Inspired Chalcogenide Semiconductors for Thin-Film Photovoltaics (Invited)D. Mitzi*1

1. Duke Univ., USA

This talk will follow the emergence of several promising thin-film photovoltaic technologies based on earth-abundant Cu2ZnSn(S,Se)4 (CZTS), Cu2BaSn(S,Se)4 (CBTS) and related I2–II–IV–VI4 structures comprising interconnected metal (subset of I, II, IV) chalcogenide (VI) tetrahedra. Simple solution- and vacuum-based film deposi-tion approaches enable fabrication of well-formed absorber layers, with resulting device sunlight-to-electricity power conversion effi-ciencies currently exceeding 12% for the kesterite-structured CZTS and 5% for CBTS. For the CZTS system, the close chemical simi-larity between, for example, Cu and Zn promotes anti-site disorder within the films, contributing to reduced device open circuit voltage. In CBTS, the much larger Ba ion occupies a site with 8-fold coordination, reducing the probability of anti-site disorder with Cu/Sn (which still maintain a tetrahedrally-coordinated network). A similar arrangement has recently been shown to apply for the broader I2–II–IV–VI4 (I = Cu, Ag; II = Sr, Ba; IV = Ge, Sn; VI = S, Se) family. Although at an early stage of development, the concept of employing atomic size and coordination discrepancy for limiting anti-site disorder (as in CBTS) may offer a pathway for overcoming performance issues encountered within complex kesterite-related multinary chalcogenide semiconductors for photovoltaic (as well as photoelectrochemical) application.

11:00 AM(EAM-ELEC-S1-003-2018) Functional electronic responses from chalcogenide materials: New opportunities (Invited)A. M. Rappe*1

1. University of Pennsylvania, Chemistry, USA

Chalcogenide materials are experiencing a Renaissance, because they combine many of the favorable properties of oxide ceramics with new structural and electronic features. In this lecture, I will draw analogies between the chalcogenides and oxides on the basis of three-dimensional materials modeling. I will then discuss extensions to layered bulk materials as well as two-dimensional sheets. First-principles calculations offer a unique window into the structural, electronic, and optical properties of materials. Insights from elec-tronic structure analysis of oxides, oxysulfides, sulfides, selenides, and tellurides will be offered. Predictions about electric polarization and bulk photovoltaic currents will be provided. The opportunities for tailoring electronic properties through chemical composition modification and dimensionality crossover will be highlighted.

11:30 AM(EAM-ELEC-S1-004-2018) Complex Sulfide Materials for Electrochemical Energy Storage Applications (Invited)R. Seshadri*1

1. University of California Santa Barbara, Materials, USA

I will discuss our recent results on the use of transition-metal sulfides and related materials as electrodes as lithium battery electrodes. Sulfur cathodes in conversion reaction batteries offer high gravi-metric capacity but suffer from parasitic polysulfide shuttle, which I will briefly describe. Transition metal chalcogenide compounds may help to mitigate such shuttle, providing interesting situations where, in contrast to many batter-electrode materials, the redox on the electrode in is anion-centered. I will discuss the use of iron and cobalt pyrites as electrodes and discuss how in-situ and ex-situ char-acterization methods help unravel the mechanisms associated with cycling. Other sulfide materials, including chalcogels will also be discussed.


Imaging and Analytical Techniques IRoom: Magnolia A/BSession Chairs: David McComb, The Ohio State University; Arno Merkle, XRE

10:00 AM(EAM-ELEC-S3-001-2018) Oxide scale structures and mechanisms of oxidation on Ni and Ti alloys (Invited)T. Barth1; K. Chou1; P. Chu1; E. Marquis*1

1. University of Michigan, USA

Lifetimes of structural alloys used in high temperature applications are often limited by their vulnerability to oxidation. To address this issue, different alloying and/or coating strategies are available depending on alloy system and application. Alloy chemistries may be tailored so a slow-growing, passive oxide scale forms on the alloy surface and protects it from further attack by oxidation. This is the case of Cr and Al additions forming protective chroma and alumina scales on Ni and Fe alloys. For Ti alloys that are particularly susceptible to oxidation, intermetallic coatings are being explored as a mean to provide oxidation protection. Additional minor alloying additions may also be used. It is well-established that the addition of


Abstracts

small amounts of specific dopants in Ni alloys can result in a signifi-cant improvement in the scale lifetime due to reduced oxide growth kinetics and enhanced scale adherence. Though significant phenom-enological knowledge exists regarding alloying, doping, and coating strategies, a mechanistic understanding of the role of alloying on oxide scale formation and evolution is often lacking. Therefore high resolution characterization techniques, including transmission elec-tron microscopy and atom probe tomography, provide a unique opportunity to uncover new insights into the structure and evolu-tion of oxide scales, and ultimately quantify mechanisms of alloy oxidation.

10:30 AM(EAM-ELEC-S3-002-2018) Characterization of Advanced Materials using X-ray Tomography and X-ray Fluorescence (Invited)B. M. Patterson*1; K. Henderson1; N. Cordes1; J. Mertens1; J. Williams2; N. Chawla2; X. Xiao3

1. Los Alamos National Lab, Materials Science and Technology, USA2. Arizona State University, 4D Materials Science, USA3. Argonne National Lab, X-ray Sciences Division, USA

The use of X-ray techniques to characterize advanced materials, their starting morphology, elemental composition & distribution, and in situ morphological changes is critical to connecting the struc-ture-property relationships. Probing that relationship is crucial to understanding how the formulation affects the ultimate character-istics of the material. X-ray tomography allows materials scientists to non-destructively probe the structure and composition of mate-rials, while also examining the dynamic deformation. X-ray CT, an indispensable tool for materials development and characterization, acquires 3D images, non-destructively, providing an image of its internal 3D structure on features as small as 150 nm to multi-mm in scale or on time frames as short as 0.25 seconds per 3D image. This provides a better understanding of its manufactured morphology, after-experiment morphology, and even the morphological changes during the experiment. This technique is critical to understanding microstructure and fracture in 3D printed composites. Additionally, the use of 2D and 3D confocal micro X-ray fluorescence allows scientists to spectrally identify and spatially map the elemental composition of materials. The 3D mapping of subsurface particles and layers, correlated with X-ray CT, provides a complete picture of the morphology and composition of electrical circuit components.

11:00 AM(EAM-ELEC-S3-003-2018) Leveraging Navigation and Sampling Strategies for Multiscale Imaging and Characterization of Functional Materials (Invited)W. Harris*1; L. Lavery1; H. Bale1; T. Volkenandt1; S. Freitag1

1. Carl Zeiss Microscopy, USA

In the materials characterization lab, a variety of instruments have emerged to address particular length scales or characteristics of materials. Simultaneously, most material systems under investiga-tion have become increasingly multiscale, leveraging and exploiting complex relationships between nano/microscale structure and system-level properties and performance. As a result, the researcher is faced with the challenge of extracting a broad spectrum of infor-mation, often from targeted regions of interest, by utilizing multiple characterization tools. In this paper, the multiscale and multimodal characterization challenge in microscopy will be presented alongside some of the emerging techniques to address these needs in a coor-dinated and efficient manner. Integrated correlative methods, in 2D as well as 3D, are opening the door for intelligent, targeted charac-terization of specific ROIs while moving through the length scales, empowering the microscopist to: determine the correct locations for the next stage of investigation; easily co-locate data from different modalities to improve understanding; and critically maintain the contextual significance of small isolated locations within the extent

of a larger sample. These advances have implications for future char-acterization of functional ceramics and beyond, and will be explored by means of several examples.

11:30 AM(EAM-ELEC-S3-004-2018) Development of Multiscale Correlative 3D Imaging for CeramicsD. W. McComb*1; I. Boona1

1. The Ohio State University, USA

Many materials challenges require an understanding on multiple length scales and often visualization in three dimensions (3D) is essential. For example, composites found in lithium ion batteries, catalytic systems and even mineralized tissue are comprised of organic and inorganic phases with many channels, pores, and features that span length scales from centimeters to nanometers. Fully characterizing these complex structures requires the use of correlative microscopy applied to a sufficiently broad range of tech-niques that can span the full range of length scales involved. In this contribution we will discuss development of a multiscale correla-tive workflow that combines X-ray microtomography (XMT) with FIB-SEM and scanning transmission electron microscopy (STEM). The workflow process developed is being used to understand the 3-D structure of human dentin and is also being employed to study the microstructural evolution of complex cathodes in lithium-ion batteries as a function of electrochemical cycling. In this case, the correlative datasets obtained provide a platform for the development of a predictive model for battery design. The techniques developed here may also be used to perform multiscale correlative imaging studies in other materials systems ceramic systems such as sensors and composites.

11:45 AM(EAM-ELEC-S3-005-2018) Ferroelectric Domain Continuity over Grain BoundariesS. Mantri*1; J. Oddershede3; D. Damjanovic2; J. Daniels1

1. University of New South Wales, Materials Science and Engineering, Australia

2. EPFL, Switzerland3. Xnovo Technology, Denmark

Grain boundaries limit the macroscopic ferroelectric properties of bulk polycrystalline ferroelectrics by restricting the mobility of domain walls. Domain wall continuity across grain boundaries has been observed since the 1950’s and is speculated to change the grain boundary-domain wall interactions. The collective ferroelectric response of neighboring grains observed in thin films might also be due to correlated domain structures. The full 5-dimensional nature of the grain boundary must be accounted for in order to under-stand domain wall interactions. In this work, we have utilized the previously developed mathematical requirements for domain wall plane matching along with simultaneous calculation of resultant ferroelectric polarization charge at grain boundaries for calculation of the probability of domain plane continuity for specific neigh-boring grain combination [1]. We have extended this analysis to cover all possible grain neighbor in a tetragonal ferroelectric. The presentation will furthermore be extended to encompass other ferro-electric symmetries, including, orthorhombic and rhombohedral. By utilizing 3D microstructural mapping methods like sectioned EBSD and 3D-XRD and calculating the 5-dimensional grain boundary character, we can apply this knowledge to optimize processing tech-niques to result in desired interactions between grain boundaries and domain walls.


Abstracts

ELECTRONICS DIV S7: Mesoscale Phenomena in Ceramic Materials

Mesoscale Phenomena in Ceramic MaterialsRoom: Cypress A/BSession Chairs: Edward Gorzkowski, Naval Research Lab; Serge Nakhmanson, University of Connecticut

10:00 AM(EAM-ELEC-S7-001-2018) Mesoscopic Modeling of Electrocaloric, Elastocaloric and Flexocaloric Properties of Ferroelectrics (Invited)P. Alpay*1; T. Patel1; H. Khassaf1


There is a need for the development of comprehensive, multi-scale theoretical tools in the search for better materials. This is essentially at the core of the recent “materials genomics/informatics” initia-tives that seek to accelerate materials discovery through the use of computations across length and time scales, and supported by exper-imental work. Such methods will result in customizing, or entirely replacing, existing engineering metallic alloys, polymers, and ceramics that were developed based on trial-and-error approaches in the past century. In this talk, we will apply these principles to understand pyroelectric, electrocaloric, elastocaloric, and flexoca-loric properties of ferroelectric materials. Pyroelectrics can convert heat into electricity by cycling around thermally- and electrically- induced polarization changes, in which the energy density scales with the product of the polarization change and applied field. The challenges in realizing caloric energy conversion system are multi-scale and multi-faceted: requiring a combination of first principles computations, phenomenological theory, classical thermodynamics, materials synthesis, and eventually systems design. We will discuss our successes and challenges by comparing materials properties of modeled and measured values for bulk and epitaxial thin film ferroelectrics.

10:30 AM(EAM-ELEC-S7-002-2018) New developments in Ferret, an open-source code for simulating complex behavior of electroactive materials at mesoscaleJ. Mangeri1; L. Kuna1; K. Pitike2; P. Alpay2; O. Heinonen3; S. Nakhmanson*2

1. Univeristy of Connecticut, Physics, USA2. University of Connecticut, Materials Science and Engineering, USA3. Argonne National Laboratory, USA

Ferret is an open-source highly scalable real-space finite-ele-ment-method (FEM) based code for simulating transitional behavior of materials systems with coupled physical properties at mesoscale. This code is built on MOOSE, Multiphysics Object Oriented Simulation Environment, that is being developed by Idaho National Laboratory. In this presentation we provide an overview of computational approach utilized by the code, and highlight its new simulational capabilities introduced over the past year, with a focus on electro-optic, elasto-optic (photoelastic) and polar-optic couplings. We then showcase a number of computational projects conducted utilizing the code that include (a) evaluations of size-, shape- and geometry-dependent elastic and optical properties of monolythic and core/shell semiconducting nanowires; (b) studies of piezoelectric response in perovskite-ferroelectric nanoislands, (c) investigation of topological phases and field-induced response in ferroelectric nanoinclusions of different shapes and sizes embedded in a dielectic matrix, and (d) calculations of birefringence and refractive index tuning by applied electric and elastic fields in poly-crystalline piezoelectric and ferroelectric materials.

10:45 AM(EAM-ELEC-S7-003-2018) Real nanoparticles have curves: Exploring polar phase transformations in Superellipsoidal nanoparticlesH. Whitelock*1; K. Pitike2; J. Mangeri1; T. Patel2; P. Dyer2; P. Alpay2; S. Nakhmanson2

1. University of Connecticut, Physics, USA2. University of Connecticut, Materials Science & Engineering, USA

Recent advances in ferroelectric nanoparticle synthesis allow for precise control of shape, size and morphology. Motivated by these developments, we have conducted a thorough theoretical/compu-tational analysis of polar phase transitions in these nanoparticles as a function of shape and size. In this investigation, we utilized a time-dependent Ginzburg-Landau approach combined with coupled-physics finite-element-method based simulations to study members of the superellipsoidal shape series, including octahe-drons, spheres and cubes, as well as intermediate shapes occuring between octahedron and sphere, and sphere and cube. Perovskite PbTiO3 was used as the generic ferroelectric material comprising the particles, which are embedded in a linear elastic-dielectric matrix of SrTiO3. We find that in non-spherical particles the topology of the polarization texture within the particle is highly sensitive to its shape, symmetry and size. These computational studies can serve as guide for focused nanoparticle synthesis or investigations of possible design rules for implementing novel functionality in devices.

11:00 AM(EAM-ELEC-S7-004-2018) Predicting ferroelectric phase-transition temperatures in perovskite oxides: Influence of exchange-correlation functional choiceK. Pitike*1; S. F. Yuk2; Y. Li3; M. Eisenbach3; S. Nakhmanson1; V. R. Cooper2

1. University of Connecticut, Materials Science and Engineering, USA2. Oak Ridge National Laboratory, Materials Science and Technology

Division, USA3. Oak Ridge National Laboratory, National Center for Computational

Sciences, USA

ABO3 perovskite-oxide ferroelectrics are well known for their useful functional properties. These materials, as well as their solid solu-tions, exhibit rich phase diagrams that can be exploited, e.g., to obtain large piezoelectric and dielectric responses. Because of the complex behavior displayed by these materials, availability of meso-scale-level parameterizations capable of accurately reproducing their properties at finite temperature is quite limited. With a general goal to determine all of the necessary parameters directly from first principles, e.g., from the density-functional theory (DFT) calcula-tions, here we investigate the influence of the exchange correlation (XC) functional choice on the prediction of ferroelectric transition temperature in PbTiO3. LDA, PBE, PBEsol and vdW-DF-C09 XC functionals are evaluated utilizing constant-temperature molecular dynamics simulations. We find that LDA, PBEsol and vdW-C09 functionals provide good estimates of the transition temperature, as compared with its experimental value, while PBE functional overes-timates the transition temperature by a significant amount.

11:15 AM(EAM-ELEC-S7-005-2018) Mesoscale modeling of electro- and elasto-optic effects in polycrystalline ceramicsL. Kuna*1; J. Mangeri1; E. Gorzkowski2; J. Wollmershauser2; S. Nakhmanson3

1. University of Connecticut, Physics, USA2. Office of Naval Research, USA3. University of Connecticut, Institute of Materials Science, USA

Non-centrosymmetric ceramic crystals are particularly interesting for tunable optical applications because they exhibit birefrin-gence and their optical properties can be modulated by external electric and mechanical fields due to electro- and elasto-optic effects. Furthermore, light transmittance through polycrystalline


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incarnations of these materials can be affected by a number of different factors, including scattering off of pores and other defects, as well as by large changes of the refraction index across grain boundaries. In this study, we utilize a mesoscale finite-element based modeling approach to investigate the properties of two archetypical non-centrosymmetric optical materials, such as zinc oxide (ZnO) and potassium dihydrogen phospate (KDP). A simple bicrystal interface setup is used to determine the transparency (or opacity) of polycrystalline ZnO and KDP samples, and elucidate the effects of changing crystallographic orientations across the interface, and the influence of applied electric and elastic fields.

11:30 AM(EAM-ELEC-S7-006-2018) Effect of Ga-V co-doping in dielectric properties of TiO2

N. Khatun*1; S. Sen1

1. Indian Institute of Technology Indore, Physics, India

Ga-V co-doped TiO2 samples are prepared by the modified sol-gel process. The phase formation of the samples is confirmed by X-ray diffraction spectroscopy. The content of Ga and V in the samples is confirmed by EDX measurement. SEM images of the fracture surface of the pellet show that all samples are well dense. Dielectric prop-erties of these samples are measured by impedance spectroscopy in the frequency range of 1Hz to 1 MHz. Pentavalent Vanadium doping in TiO2 increases the dielectric constant while dielectric loss also increases. In case of trivalent gallium doping dielectric constant decreases and with that dielectric loss also decreases. Here combine effect of trivalent and pentavalent doping (Ga-V) in TiO2 increase the dielectric constant and decrease the dielectric loss.

11:45 AM(EAM-ELEC-S7-007-2018) Electric Properties of Thermally Grown TiO2 Layer on Ti Metal for Perovskite Solar CellsS. Lee*1; J. Lee1

1. University of Pittsburgh, Mechanical Engineering and Materials Science, USA

In perovskite solar cells (PSC), the halide layer is coated on meso-porous or planar TiO2 that plays a role of an electron transport layer (ETL). Commonly, TiO2 layer is deposited on F-doped SnO2 and thermally annealed above 400 oC or higher. However, this process cannot be applied to the polymer substrates that are used for flex-ible solar cells. Metal plates with thermally oxidized surface can be an attractive alternative, because of their high temperature process capability and excellent mechanical property. In this presentation, we report the electric properties of a very thin (<100 nm) TiO2 layer on oxidized Ti metal plate and their effect the performance of highly bendable PSCs. The concentration of oxygen vacancies in the oxidized TiO2 layer is found to control the electric function of ETL of PSCs. A decrease in the oxygen vacancy concentration of TiO2 layer is key to improving the electron collection efficiency. Power conversion efficiency (PCE) reaches 14.9 % with open circuit voltage (Voc) of 1.09, and fill factor (ff) of 0.74. High ff and Voc are attributed to high crystalline quality and low oxygen vacancy concentra-tion of TiO2 layer. Moreover, the Ti metal based PSCs exhibit an outstanding fatigue resistance.


Coupling between Ferroelectricity and FerromagnetismRoom: Orange DSession Chair: Daisuke Kan, Institute for Chemical Research

10:00 AM(EAM-ELEC-S8-009-2018) Room temperature strain and charge-mediated magnetoelectric effects in multiferroic complex oxide heterostructures (Invited)R. V. Chopdekar*1; Y. Takamura1

1. University of California, Davis, Materials Science and Engineering, USA

Research towards room-temperature magnetoelectric effects in artificial multiferroic systems aims to circumvent limitations of single-phase multiferroics. In particular, epitaxial manganites offer the ability to tune functional properties through lattice, charge, spin and orbital degrees of freedom. Our work on (011)-oriented Pb(Mg,Nb,Ti)O3 (PMN-PT)/(La,Sr)MnO3 heterostructures showed significant magnetization changes upon substrate poling, due to strain-driven changes in eg electron itinerancy and magnetoelastic anisotropy energy. Rotation of the PMN-PT ferroelectric axis induces an anisotropic, non-volatile strain tuning in thick (La,Sr)MnO3 films corresponding to a 5% change in room temperature resistivity. In thin films, electrostatic doping from the substrate polarity dominates, resulting in a 6% change in resistivity. Carrier photoinjection from a laser diode effectively screens ferroelectric interface charge and modulates the electrostatic doping effect by 30% in thin films, whereas there is little change in strain-modu-lated resistivity of thick films. Thus, artificial multiferroic systems show large room temperature resistive and magnetic changes through simultaneous strain and charge mediated effects, encour-aging investigation of such materials for multifunctional devices tunable through magnetic and electric fields as well as visible-light illumination.

10:30 AM(EAM-ELEC-S8-010-2018) New Vertical Aligned Nanocomposite Films with Strong Room Temperature Converse Magnetoelectric Effect (Invited)R. Wu*1; S. Cho1; A. Kursumovic1; J. MacManus-Driscoll1

1. University of Cambridge, United Kingdom

Vertically aligned nanocomposites (VANs) with the 3-1 structure, containing ferroelectric and ferro/ferrimagnetic materials, have the possibility to achieve magnetoelectric coupling for ultra-high density magnetic recording with low-power electric-writing via voltage driven magnetization switching. So far, the BaTiO3-CoFe2O4 (BTO-CFO) and BiFeO3- CoFe2O4 (BFO-CFO) VANs have been intensively studied. However, the relatively low Curie temperature of BTO (Tc of 393 K) and large leakage in the BFO limits device appli-cations. Therefore, new materials and precise nanoengineering of these new materials is required. In this work, we have explored alter-native high Tc ferroelectrics and CFO in a new VAN system. The leakage problem is overcome by exploiting several new features in the system. Both excellent ferroelectric properties and ferrimagnetic properties are achieved. Strong converse magnetoelectric coupling is achieved in this system, enabling the control of magnetism with in-situ electric field at room temperature.


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11:00 AM(EAM-ELEC-S8-011-2018) Tuning Spin Relaxations in Ultrathin Epitaxial SrIrO3 Thin Films via Ferroelectric GatingL. Zhang*1; M. Han2; X. Zhang1; X. Jiang1; X. Xu1; Y. Zhu2; X. Hong1

1. University of Nebraska - Lincoln, Physics and Astronomy, USA2. Brookhaven National Laboratory, Condensed Matter Physics and

Materials Science, USA

As the end member of the Ruddlesden-Popper series, SrIrO3 (SIO) remains paramagnetic, semimetallic and with nontrivial topolog-ical properties. Its strongly correlated nature and large spin orbital coupling (SOC) make SIO a promising material candidate for spintronic applications. As a feature of strong SOC, weak anti-local-ization, manifested as negative quantum interference correction to the conductance, has been observed in the magnetoresistance (MR) at low temperatures. Using the Maekawa-Fukuyama model, we have extracted inelastic scattering and spin precession length, which show distinct temperature dependences. Moreover, the linear mobility dependence of spin precession time points to Elliott-Yafet mecha-nism as the dominant spin relaxation mechanism. By fabricating the PbZr0.2Ti0.8O3 (PZT)/SIO (∼2 nm) heterostructures, we have demonstrated nonvolatile resistance change in SIO via switching the polarization of PZT. We extracted the carrier density and mobility based on the Hall measurements combined with the MR, which reveals tuning of the nearly compensated electron- and hole- densities. The onset temperature of the resistance upturn is also modulated by ferroelectric field effect, with a 10 K shift observed. The modulation of MR indicates the change of SOC strength in SIO. Our results demonstrate a feasible way to manipulating the SOC at the interface of all oxides heterostructures.

11:15 AM(EAM-ELEC-S8-017-2018) Emergent and Tunable Toroidal Order and Phase Coexistence in Ferroic Superlattices (Invited)L. W. Martin*1


In superconductivity, colossal magnetoresistance, and multiferroism emergent phenomena arise from the interplay of various degrees of freedom and competing phases that drive nanoscale complexity (i.e., chemical, ionic, electronic, etc. variations) that can be readily controlled using external stimuli to produce colossal changes in physical responses. We will explore similar effects in superlattices of (PbTiO3)n/(SrTiO3)n, wherein Landau, electrical, elastic, and gradient energies are placed into competition to drive polarization vortex formation. We will explore a number of aspects: 1) The observa-tion of phase coexistence mediated by a first-order phase transition between an emergent, low temperature vortex phase with electric toroidal order and a high-temperature ferroelectric a1/a2 phase. 2) The room-temperature coexistence of vortex and ferroelectric phases in a mesoscale, fiber-textured hierarchical superstructure. 3) The identification of a multi-order-parameter state and belongs to a class of gyrotropic electrotoroidal compounds. 4) That application of electric fields to this mixed-phase system permits interconversion between the vortex and the ferroelectric phases concomitant with order of magnitude changes in piezoelectric and nonlinear optical responses. This work suggest new cross-coupled functionalities and we will explore the potential for exotic optical and dielectric response.

11:45 AM(EAM-ELEC-S8-013-2018) Revealing the hidden magnetic interfaces by polarized neutron reflectometry (Invited)E. Guo*1

1. Oak Ridge National Lab, USA

In this talk, firstly, I will show the evolution of the magnetic moment at interfaces in the typical ferroelectric/ferromagnetic (PbZr0.2Ti0.8O3/La0.8Sr0.2MnO3, PZT/LSMO) oxide heterostructures

using polarized neutron reflectometry (PNR). The magnetizations of LSMO at both surface and interface are deteriorated; however, such deterioration can be much improved by interfacing with a ferroelectric. Assisted by ionic liquids (ILs), the interfacial magneti-zation of LSMO can be reversibly controlled by electrically switching the ferroelectric polarization. The compelling results demonstrate the strong modulation of magnetization by charge density at the interface. The second part of my talk, I identify the large interfacial magnetization in BiFeO3 (BFO) layers only exists in close proximity (~ 3 - 4 unit cells) to the LSMO. The enhanced magnetization in BFO is only observed in the [100]-orientation, however, is absent in the [111]-orientations. Moreover, the induced magnetic moment in BFO is proportional to the magnetization of the adjacent ferro-magnet. We attribute the induced large net magnetization in BFO is a result of orbital reconstruction between Fe and Mn across the interface, which establishes an upper temperature limit for magnetic ordering temperature of BFO.


Substitition and Sustainability in Functional Materials IIRoom: Citrus BSession Chair: Ian Reaney, University of Sheffield

10:00 AM(EAM-ELEC-S9-010-2018) High Temperature Dielectric and Pb-free Piezoelectric Ceramics based on Relaxor Ferroelectrics: Properties and Challenges in Determining Mechanisms (Invited)A. Zeb3; Z. Aslam1; A. Brown1; R. Brydson1; J. Forrester1; D. A. Hall2; S. ullah Jan3; T. Roncal-Herrero1; S. J. Milne*1

1. University of Leeds, Materials, United Kingdom2. University of Manchester, School of Materials, United Kingdom3. Islamia College, Pakistan

Ceramics with stable and high relative permittivity, combined with low dielectric loss over wide temperature ranges, for example from -55 °C to 300 °C, are required as capacitor materials for energy- related applications. Developments in the performance of materials will be summarised and their relevance to the demands of a working high temperature capacitor discussed. Results of preliminary inves-tigations of nanostructure using scanning transmission electron microscopy will be presented.

10:30 AM(EAM-ELEC-S9-011-2018) High strain (0.4%) Bi(Mg2/3Nb1/3)O3-BaTiO3-BiFeO3 lead-free piezoelectricsS. Murakami*1; A. Mostaed1; D. Wang1; A. Khesro1; A. Feteira2; D. C. Sinclair1; I. M. Reaney1

1. The University of Sheffield, Materials Science and Engineering, United Kingdom

2. Sheffield Hallam University, Materials Engineering and Research Institute, United Kingdom

BaTiO3-BiFeO3 based ceramics are promising lead-free piezoelectric candidates. To investigate the effect of the self-compensated dopant (Mg2/3Nb1/3) with a view to optimising piezoelectric properties, research was carried out on the structure/microstructure property relations for 0.05Bi(Mg2/3Nb1/3)O3-(0.95-x)BaTiO3-(x)BiFeO3 (BBFT, x = 0.55, 0.60, 0.63, 0.65, 0.70, 0.75) ceramics. X-ray diffraction suggested a structural transition from pseudocubic to rhombohedral for 0.63<x<0.70. The temperature dependence of relative permit-tivity, PE hysteresis loops, bipolar SE curves, and TEM indicated that BBFT transformed from relaxor-like to ferroelectric behaviour with


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an increase in x. The largest strain was 0.41% for x = 0.63 at 10kV/mm in unpoled samples but the largest effective piezoelectric coefficient (d33

*) was 544 pm/V for x = 0.63 at 5 kV/mm after poling for 20 mins under 5kV/mm at 100°C. We propose that d33

* is optimised at the point of crossover from relaxor to ferroelectric which facilitates a macroscopic field induced transition to a ferroelectric state.

10:45 AM(EAM-ELEC-S9-012-2018) High Temperature PbO-free PiezoelectricsI. M. Reaney*1


There are numerous PbO-freeceramics whose properties are opti-mised at <100 oC. Although still not as good as lead-based materials, an argument can be made that several PbO-free compositions could satisfy some existing room temperature piezoelectric applications. However, there is a a paucity of PbO free materials that operate at >150 oC since the two dominant systems based on sodium bismuth titanate and potassium sodium niobate either depole or their piezo-electric activity drops away alarmingly on heating to >150 oC. This presentation reviews the state of the art of PbO-free piezozelectrics and highlights two systems based on potassium bismuth titanate and BaTiO3 - BiFeO3 which show promise for applications at >150 oC. In addition, a generic crysallochemical mechanism is proposed for why such compositions exhibit large effective strains suitable for high temperature actuator applications.

11:00 AM(EAM-ELEC-S9-013-2018) Suppression of electrical conductivity and switching of conduction mechanisms in ‘stoichiometric’ (Na0.5Bi0.5TiO3)1−x(BiAlO3)x (0 ≤ x ≤ 0.08) solid solutionsF. Yang2; Y. Wu2; D. C. Sinclair*1


2. University of Sheffield, United Kingdom

(Na0.5Bi0.5TiO3)1−x(BiAlO3)x (0 ≤ x ≤ 0.08) solid solutions were prepared by a solid state reaction and their electrical properties were established by ac impedance spectroscopy and electromotive force transport number measurements. Incorporation of BiAlO3 (BA) decreases the electrical conductivity of Na0.5Bi0.5TiO3 (NBT) and sequentially changes the conduction mechanism with increasing x from predominant oxide-ion conduction to mixed ionic–electronic conduction and finally to predominant electronic conduction. The suppressed oxide-ion conduction by BA incorporation significantly reduces the dielectric loss at elevated temperatures and produces excellent high-temperature dielectric materials for high BA contents. The possible reasons for the suppressed oxide-ion conduction in the NBT–BA solid solutions will be discussed and we propose that the local structure, especially trapping of oxygen vacancies by Al3+ on the B-site, plays a key role in oxide-ion conduction in these appar-ently ‘stoichiometric’ NBT-based solid-solution perovskite materials.

11:15 AM(EAM-ELEC-S9-014-2018) Aqueous Deposition of Thin Film Potatssium Sodium Niobate Using Simple Cluster PrecursorsD. Fast1; M. Clark1; M. Dolgos*1

1. Oregon State University, Chemistry, USA

Sustainability and environmental concerns are becoming increas-ingly important in materials science as electronic devices become more ubiquitous and plentiful around the globe. Ferroelectric devices rely predominately on lead zirconium titanate but due to toxicity and performance limitations, there is a desire to move away from lead containing materials. For this reason alternatives to the widely used PZT are highly sought after and the focus of much ferroelectric research. Due to its high d33 and Tc Potassium

sodium niobate (KNN) is a promising and often studied candidate for replacing PZT. KNN has classically been made through solid-state methods and thin films are often synthesized using a sol-gel approach, which presents significant complications due to air and moisture sensitivity. This research presents a simple synthetic method using a one-pot precursor that leverages aqueous polyoxo-metalate chemistry. The Nb Lindqvist ion was crystallized as a salt with the composition X8Nb6O19 (X=Na, K). The salt re-dissolves easily in water and deposits homogenously using spin-coating. The films readily crystallize at temperatures of ~700°C and grow epitaxially on STO to the desired KNN composition. Film quality was evaluated through electron microscopy, X-ray diffraction, and atomic force microscopy. Electrical/ferroelectric properties were measured to evaluate the film performance.

11:30 AM(EAM-ELEC-S9-015-2018) Electronic and Ionic Conduction in (Bi0.5Na0.5)TiO3-(Bi0.5K0.5)TiO3–based Thin Films (Invited)J. Walenza-Slabe1; A. Fox1; K. Grove1; M. Bahmer1; B. Gibbons*1

1. Oregon State University, USA

Pb-free piezoelectrics continue to be an area of active investiga-tion, however the optimization of thin film embodiments of these compositions is not comparable in scope or depth to that for mate-rials systems such as BaTiO3 and Pb(Zr,Ti)O3. Here we report on Bi(Na,K)TiO3-based thin films fabricated by chemical solu-tion deposition on Pt/Si substrates. Ternary end members such as Bi(Mg,Ti)O3 and dopants such as Mn were added to assess their effects on the piezoelectric properties and leakage current character-istics, as these additions have been shown to enhance bulk behavior. Leakage current as a function of temperature was investigated after doping with up to 2 mol% Mn. We report on transient currents and the primary conduction mechanisms from room temperature to 180 °C. Undoped films showed space-charge-limited current at high temperatures, but with addition of 2 mol% Mn the current response was fully Ohmic up to 430 kV/cm at 180 °C. All films exhibited shallow trap levels and high trap concentrations. The electric field marking the transition from Ohmic to trap-filling-limited current increased monotonically with Mn-doping. Transient currents in undoped films are related to oxygen vacancy migration, which modulates the electronic conductivity. Mobility and thermal acti-vation energy for oxygen vacancies were calculated as µion≈1.7x10-12 cm2V-1s-1 and EA,ion≈0.92 eV, respectively.

12:00 PM(EAM-ELEC-S9-016-2018) Electron transport and visible light absorption in a plasmonic photocatalyst based on strontium niobateD. Wan*1; B. Yan1; T. C. Asmara2; M. R. Motapothula1; T. V. Venkatesan1

1. National University of Singapore, NUSNNI, Singapore2. National University of Singapore, Singapore Synchrotron Light Source,

Singapore

Semiconductor compounds are widely used for photocatalytic hydrogen production applications, where photogenerated elec-tron-hole pairs are exploited to induce catalysis. Recently, powders of a metallic oxide (Sr1-xNbO3, 0.03 < x < 0.20) were reported to show competitive photocatalytic efficiencies under visible light which was attributed to interband absorption. This discovery expanded the range of materials available for optimized performance as photo-catalysts. Here we have studied epitaxial thin films of SrNbO3+δ and found that their bandgaps are ~4.1 eV. Surprisingly the carrier density of the conducting phase exceeds 1022 cm-3 and the carrier mobility is only 2.47 cm2 V-1 s-1. Contrary to earlier reports, the visible light absorption at 1.8 eV (~688 nm) is due to the plasmon resonance, arising from the large carrier density. We propose that the hot electron and hole carriers excited via Landau damping (during the plasmon decay) are responsible for the photocatalytic property of this material under visible light irradiation.


Abstracts

12:15 PM(EAM-ELEC-S9-017-2018) Simulations of High Entropy Materials (Invited)C. Freeman*1; G. Anand1; C. Handley1; R. Ward1; J. Harding1

1. University of Sheffield, Dept of Materials Science and Engineering, United Kingdom

Within the functional ceramics community we are increasingly seeing complex solid solutions containing multiple cations. These solid solutions can produce exciting properties and, depending on their components, offer solutions to sustainability by removing the need for rare or expensive dopants. This realm of solid solu-tions opens up new challenges to materials scientists: variable stoichiometry over nanometre scales; regions of disorder and cluster formation and entropic control of the thermodynamics. Classical atomic scale simulations are an idea tool for approaching these systems. The atomic level detail is essential for understanding the local relaxations that can occur around particular atomic config-urations. The relatively low cost of the simulations also means it is possible to look at multiple large cells providing the opportunity to actually sample the configurational variation that is present. The main challenge remains to ensure the simulations can make direct links to our experimental understanding of these functional ceramics. We present simulations where we look at complex solid solution systems including the recently reported high entropy oxide system. Our simulations explore the thermodynamic stability of these solid solutions and explore how large levels of disorder induce structural changes in the materials. By considering an ensemble of configurations we are able to consider the average properties these materials produce.


Lead Free Piezoelectric and Dielectrics for Energy Storage and ConversionRoom: Orange CSession Chairs: Jiwei Zhai, Tongji University; Sahn Nahm, Korea University

10:00 AM(EAM-ELEC-S13-016-2018) Enhancing Piezoelectric Properties in (K,Na)NbO3-Based Ceramics by Texture Engineering (Invited)J. Zhai*1

1. School of Materials Science and Engineering, Tongji University, China

Crystallographic texturing of polycrystalline piezoelectric ceramics offers an effective means of obtaining high piezoelectric and ferro-electric properties. Using template grain growth (TGG) method, nucleation and epitaxial growth of the matrix particles on the template surface lead to high degree of crystal orientation. Through the optimization of sintering process and template content, the (K,Na)NbO3-based piezoelectric ceramics show high texture degree up to 90%, and significant enhanced piezoelectric properties rela-tive to their randomly oriented counterparts. Theoretical calculation based on phenomenological model suggests that the enhancement of piezoelectric activity in textured piezoceramics is partly origi-nated from the intrinsic piezoelectric anisotropy. Microstructure analysis suggests that reduced domain size and high domain wall mobility should also be responsible for the enhanced piezoelec-tric properties in textured ceramics. Great progress has been made in lead-based and lead-free piezoelectric materials by texture engi-neering, therefore the textured piezoceramics are promising for practical application.

10:30 AM(EAM-ELEC-S13-017-2018) Effect of tetragonal-pseudocubic polymorphic phase transition on the piezoelectric properties of (Na0.5K0.5)(Nb1-xSbx)O3-SrTiO3 ceramics (Invited)D. Kim1; T. Lee2; S. Cho1; K. Lee1; C. Kang3; S. Nahm*1

1. Korea University, Department of Materials Science and Engineering, Republic of Korea

2. Korea University, Nano-Bio-Information-Technology Converging, KU-KIST Graduate School of Converging Science and Technology, Republic of Korea

3. Korea Institute of Science and Technology, Electronic Materials Center, Republic of Korea

The CuO-added 0.96(Na0.5K0.5)(Nb1-xSbx)O3-0.04SrTiO3 ceramics sintered at 960oC for 10 h show the dense microstructure with high relative densities. The specimens with 0.0 ≤ x ≤ 0.04 show the orthorhombic-tetragonal polymorphic phase boundary (PPB) structure. Tetragonal-pseudocubic PPB structure was observed in the specimens with 0.05 ≤ x ≤ 0.07 and the specimen with x = 0.08 has a pseudocubic structure. The pseudocubic structure formed in these specimens is very similar to the R3C rhombohedral struc-ture. Structural variation of the specimens can be explained by the decrease of orthorhombic-tetragonal transition temperature (TO-T) and Curie temperature (TC) with the addition of Sb5+ ions. Large piezoelectric properties were observed from the specimens with the tetragonal-pseudocubic PPB structure, which is similar to the tetragonal-rhombohedral morphotropic phase boundary struc-ture observed in Pb (Zr,Ti)O3 ceramics. In particular, the specimen with x = 0.055 shows the enhanced piezoelectric properties: d33 of 365 pC/N, kp of 0.45 and electric field-induced strain of 0.16% at 4.5kV/mm.

11:00 AM(EAM-ELEC-S13-018-2018) Small-scale Flexible Energy Devices using Lead-free Piezoelectric Thin FilmsS. Kim*1; S. Won1; M. Kawahara2; C. Koo3; A. Kingon1

1. Brown University, School of Engineering, USA2. Kojundo Chemical Laboratory, Japan3. Quintess Co. LTd., Republic of Korea

The objective of this research is to develop a new class of eco-friendly small-scale flexible energy devices using bio-compatible lead-free piezoelectric thin films, with the emphasis on self-power genera-tion and high energy storage capabilities. Our research addresses the critical need for autonomous power to replace or recharge the batteries that power the current electronic devices. We demonstrate a new approach for improving the power generation and energy storage capacity of the devices via cost effective chemical solution- derived lead-free piezoelectric thin films coupled with medical grade flexible substrates. Several materials and process innovations are integrated to provide a robust platform to expand the performance of the important category of energy harvesting and storage systems, and the platform is also more broadly applicable to size-scaled and low cost flexible electronic systems. Our new approach for bio- compatible and flexible energy device systems with the size and the weight of the smallest scale provides an advanced processing and design platforms to dramatically expand the capability of high power and high energy density devices, and also explores the addition of new functionality to current and future power electronic systems.


Abstracts

11:15 AM(EAM-ELEC-S13-019-2018) Lead-free Piezoelectric Thin Films: Materials and DevicesS. Won*1; C. Koo3; A. Kingon1; S. Kim2

1. Brown University, USA2. Brown University, School of Engineering, USA3. Quintess Co. Ltd., Republic of Korea

There is a strong interest in introducing ferroelectric thin films for applications in small-scale electronic devices since they have large piezoelectric coefficients and electromechanical coupling coefficients. Among ferroelectrics, PZT films are considered the most promising candidates for the piezoelectric devices since they can produce high mechanical strain under applied electric field. However, even if PZT has various excellent piezoelectric properties, the toxicity of lead (Pb) in PZT has led to global efforts to identify a replacement system, and this search is particularly critical for environmental-friendly electronic device applications. Recently there have been a number of concepts presented for bio-compatible electronic devices with the size at the smallest scale using lead-free piezoelectric thin films. For these applications, we have investigated (K,Na)NbO3 (KNN)- and Bi(Na,K)TiO3 (BNKT)-based lead-free piezoelectric thin films using a chemical deposition method. To develop KNN- and BNKT-based thin films for piezoelectric device applications, it is necessary to have a comprehensive knowledge regarding the mechanisms contributing to the observed piezoelectric and the related electrical properties. Here, we describe the enhanced electrical properties of bio-compatible lead-free thin films and device performance in detail.

11:30 AM(EAM-ELEC-S13-020-2018) The Energy Storage Behavior of Lead Free Perovskite Dielectric CeramicsS. Zhang*1

1. University of Wollongong, ISEM, Australia

Electrical energy storage has become a key for an effective implemen-tation of the electricity generated from renewable energy sources, in order to maintain the sustainable development of the ecological society. Dielectric capacitors as an electrical energy storage tech-nology belong to passive electronic components that store energy in the form of an electrostatic field and have been widely applied in electronic circuit. Up to now, the driving force for dielectric capac-itor applications is attributed to the significantly increased consumer electronics market. Typical features of dielectric capacitors which intrinsically exhibit a high energy density and a fast charge/discharge performance compared to Li-ion batteries or fuel cells make them promising candidates for energy storage devices in some specific areas. In this presentation, recent developments on relaxor ferroelec-tric and antiferroelectric based dielectric ceramics will be surveyed, the impacts of dielectric constant, dielectric loss, dielectric break-down strength on the energy storage and reliability will be studied, which are associated with the microstructures, including density, porosity, defects, grain size and grain boundary.

11:45 AM(EAM-ELEC-S13-021-2018) Atmosphere Controlled Sintering of Textured (Na,K)NbO3 Ceramic for Enhanced Piezoelectric PropertiesL. Gao*1; S. Dursun1; E. Hennig2; S. Zhang3; C. Randall1

1. Pennsylvania State University, USA2. PI Ceramic GmbH, Germany3. University of Wollongong, Australia

(Na, K)NbO3 (NKN) has been widely studied during the past decades. Currently, the PZT based ceramics dominate the soft piezo-electric applications. However, the concern on both healthy and environmental issues of lead have been raised. European Union set the limitations on the amount of lead used in electrical and electronic

equipment (EEE). The piezoelectric industry has continually existed as an exemption under the restriction. Although NKN has excellent piezoelectric properties, it is still inferior to Pb-based soft piezoelec-tric ceramics. Therefore, it is crucial to improve the performance of NKN to adopt it into soft piezoelectric applications. We successfully fabricated Cu co-fired NKN multilayer actuators to increase the total displacement, but it would further improve the performance by texturing the NKN ceramic. In this work, textured Li- and Ta- modified NKN was fabricated through sintering under different low pO2 atmospheric environments at a relatively low temperature using plate-like NaNbO3 templates. Highly densified NKN with ~90% Lotgering orientation factor (LOF) was obtained. Compared with the samples sintered in air, the LOF was significantly improved. The high field strain coefficient d33* was ~600pm/V of the textured NKN. The promising results also enabled the feasibility of fabricating Cu co-fired textured NKN multilayer actuators in the foreseeable future.

12:00 PM(EAM-ELEC-S13-022-2018) Growth and electrical properties of NaNbO3 thin film grown on TiN/Si substrate using PLDJ. Woo*1; T. Lee2; H. Hwang1; S. Nahm2

1. Korea University, Nano-Bio-Information-Technology Converging KU-KIST Graduate School of Converging Science and Technology, Republic of Korea

2. Korea University, Materials Science and Engineering, Republic of Korea

NaNbO3 (NN) thin films were grown on the TiN/Si substrate using pulsed laser deposition (PLD) system at various conditions. The NN films grown at low temperatures (≤ 350oC) exhibited the amor-phous phase and the NN nanocrystals were observed in the NN amorphous films grown at temperatures higher than 300oC. The resistive random access memory (ReRAM) properties were inves-tigated for the NN films grown at various temperatures. The NN film grown at 350oC exhibited a bipolar resistive switching behavior and it can be explained by the formation and rupture of the oxygen vacancy filaments. This NN film showed the excellent retention properties and the reliable endurance properties with a low power consumption. Moreover, the synaptic properties such as spike-tim-ing-dependent-plasticity (STDP), short-term-plasticity (STP), long-term-plasticity (LTP) and spike-rate-dependent-plasticity (SRDP) of the NN ReRAM devices will be discussed in this work.

12:15 PM(EAM-ELEC-S13-023-2018) Electrical leakage and loss in rare-earth modified bismuth ferrite ceramicsJ. Walker*1; M. Makarovic2; S. M. Selbach3; S. E. Trolier-McKinstry1; T. Rojac2

1. Pennsylvania State University, Materials Research Institute, USA2. Jozef Stefan Institute, Electronic Ceramics Department, Slovenia3. Norwegian University of Science and Technology, Department of

Materials Science and Engineering, Norway

An impressive number of functional properties have been discov-ered in multiferroic rare-earth modified bismuth ferrites (RE-BFO). Unfortunately use of these materials has been hampered by prob-lems with electrical loss and sample reproducibility. While A-site substitution has a dominant impact on structure and electrome-chanical properties, B-site substitution appears to be effective for controlling electrical leakage and dielectric loss. The conductance varied as a function of the RE species and concentration, increasing by ~1x106 in Sm-BFO as the composition crossed the composition-ally induced rhombohedral to orthorhombic phase boundary (i.e. from 8-16 mol%). At high electric fields however, all samples exhib-ited leaky polarization electric field loops. The addition of 0.1 wt% Co to Dy-BFO removed a Maxwell-Wagner-type relaxation from the loss in the frequency range 102-2x106 Hz, and hysteresis loops with remanent polarizations of 38 µC/cm2 showed significantly reduced leakage. Co addition thus provides an avenue for reducing the elec-trical leakage and loss of RE-BFO.


Abstracts

BASIC SCIENCE DIV S1: Computational and Data Sciences for 21st Century Ceramics Research

Ferroelectrics and Other Functional CeramicsRoom: Nautilus CSession Chair: Jeffrey Rickman, Lehigh University

2:00 PM(EAM-BASIC-S1-001-2018) Computational Understanding and Prediction of Polar States in Ferroelectric Heterostructures Using Phase-field Method (Invited)L. Chen*1; Z. Hong1

1. The Pennsylvania State University, Materials Science and Engineering, USA

This presentation will discuss the applications of the phase-field method to understanding and discovering new mesoscale polar states that might emerge from nanoscale ferroelectric hetero-structures subject to different mechanical and electric boundary conditions. As an example, the determination of thermodynamic conditions and geometric length scales leading to the formation of ordered polar vortex lattice as well as mixed states of regular domains and vortices in ferroelectric superlattices of PbTiO3/SrTiO3 using phase-field simulations and analytical theory will be presented. Switching of these vortex lattice states might produce other transient polar states such as polar skyrmions. It is shown that the stability of these vortex lattices involves an intimate competition between long-range electrostatic, long-range elastic, and short-range polarization gradient-related interactions leading to both an upper- and a lower- bound to the length scale at which these states can be observed. We further predicted the periodicity phase diagrams that show excel-lent agreements with experimental observations by collaborators.

2:30 PM(EAM-BASIC-S1-002-2018) The search for new materials: Blending smart algorithms and deep physics (Invited)A. M. Rappe*1

1. University of Pennsylvania, Chemistry, USA

Modern techniques for computational materials searching are revo-lutionizing our ability to access and invent new functional materials. In some cases, the innovative approaches are purely computational, but in many instances the most effective search techniques blend physical insight with innovative computational approaches. In this lecture, I will narrate the components of a successful computational materials search methodology. This will include developing func-tional descriptors, improving modeling techniques, and searching materials databases. I will highlight successes in locating new mate-rials, such as ferroelectric photovoltaics, topological insulators, and negative thermal expansion materials. The interplay between simple models, first-principles models, and advanced search techniques will be highlighted.

3:00 PM(EAM-BASIC-S1-003-2018) Nanopillars with E-field accessible multi-state (N ≥ 4) magnetization with giant magnetization changes in self-assembled BiFeO3-CoFe2O4/Pb(Mg1/3Nb2/3)-38at%PbTiO3 heterostructures (Invited)D. Viehland*1; J. Li1; X. Tang1

1. Virginia Tech, Materials Science and Engineering, USA

We have deposited self-assembled BiFeO3-CoFe2O4 (BFO-CFO) thin films on (100) Pb(Mg1/3Nb2/3)0.62Ti0.38O3 (PMN-38PT) single crystal substrates. These heterostructures were used for the study of real-time changes in the magnetization with applied DC electric field (EDC). With increasing EDC, a giant magnetization change was

observed along the out-of-plane (easy) axis. The induced magne-tization changes of the CFO nanopillars in the BFO/CFO layer were about. A giant converse magnetoelectric (CME) coefficient of 1.3 x10-7 s/m was estimated from the data. By changing EDC, we found multiple (N ≥ 4) unique possible values of a stable magnetiza-tion with memory on removal of the field.

Material Interfaces: Structure, Properties and EvolutionRoom: Nautilus CSession Chair: Jeffrey Rickman, Lehigh University

4:00 PM(EAM-BASIC-S1-004-2018) Computing Grain Boundary ‘Phase’ Diagrams: Recent Progresses and Future Directions (Invited)J. Luo*1

1. University of California, San Diego, USA

This talk will review our recent progresses to compute grain boundary (GB) ‘phase’ (complexion) diagrams via several different methods. Earlier studies are reviewed [J. Am. Ceram. Soc. 95: 2358 (2012); Curr. Opin. Solid State Mater. Sci. 20:268 (2016)]. Two more recent studies computed GB diagrams to forecast (1) the formation and stability of sub-eutectic, quasi-liquid, intergranular films (IGFs) in TiO2-CuO [Acta Mater. 130: 329 (2017)] and (2) bilayer complex-ions in Ni-Bi [Scripta Mater. 130:165 (2017)]; both computed GB diagrams have been validated by experiments. Using the symmet-rical Σ 5 [210] tilt GB in Mo-Ni as a start point, we have further developed a method to combine a modified genetic algorithm with hybrid molecular dynamics and Monte Carlo simulations in semi-grand canonical ensembles to construct more realistic GB diagrams with atomistic details. Specifically, we have revealed a first-order GB phase-like transformation line, ending at a GB critical point. The GB diagrams constructed from atomistic simulations can effectively represent both low-T adsorption transitions predicted by an Ising type lattice model and the effects of high-T interfacial disordering forecasted by a phenomenological premelting/prewetting model. Ongoing work is being conducted to use a similar atomistic simula-tion method to model the behaviors of more general GBs as well as more complex ceramic materials.

4:30 PM(EAM-BASIC-S1-005-2018) Atomistic simulations of grain boundary phase transitions (Invited)T. Frolov*1; Q. Zhu4; A. R. Oganov3; R. E. Rudd1

1. Lawrence Livermore National Lab, USA3. Stony Brook University, USA4. University of Nevada, Las Vegas, USA

Recent years have seen a rapid growth of evidence suggesting that materials interfaces are capable of first-order structural transfor-mations in which the interface properties undergo discontinuous changes. Experiments have linked these transitions to abnormal grain growth in ceramics, activated sintering and liquid metal embrittlement and raised a number of fundamental questions concerning the atomic structures and kinetic properties of these interface phases. This talk will review recent advances in modeling methodology that enable discovery of grain boundary phases and predict the transitions. Applications of this methodology to several materials systems are discussed. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.


Abstracts

5:00 PM(EAM-BASIC-S1-006-2018) A Framework to Study Heterogeneous Factors that Influence Grain GrowthD. Lewis*1; A. Baskaran1

1. Rensselaer Polytechnic Institute, Materials Science and Engineering, USA

Grain growth has been a subject of study in the processing and microstructure of materials for many years. Recent advances have focused on three-dimensional topology, three-dimensional micro-structure reconstruction and three dimensional kinetic models. Much of our understanding to date is based on assumptions of uniform boundary mobility and surface energy. In this talk I will describe an enhanced framework for study of grain growth when the key factors of mobility, surface energy and curvature are not uniformly distributed in the microstructure. I will present some early modeling results and some ideas for future study.

5:30 PM(EAM-BASIC-S1-007-2018) Microstructural Evolution of Lithium Electrodeposits in Liquid Electrolytes (Invited)A. Jana*1; S. I. Woo1; K. S. Vikrant1; R. E. García1

1. Purdue University, School of Materials Engineering, USA

Dendritic growth of lithium metal on battery anodes is respon-sible for the catastrophic failure of portable electronic devices and electric vehicles. Experimental observations have qualitatively proposed tip- and base-controlled growth as the two main modes for microstructural evolution. Fundamentally, it is well known that the resultant complex morphology that the electrodeposit develops is largely due to the inherent coupling of several driving forces, including the electric field distribution, mechanical stress inhomo-geneities, and interfacial energy contributions that act to define the topology the growing lithium metal. By starting from experimen-tally observed lithium morphologies from open scientific literature, a thermodynamically consistent variational framework to capture the contributions of each driving force is developed. Different regimes of behavior are identified and summarized into 2D maps that show the major ranges of controlling electrochemical and chemomechanical stresses as the lithium electrodeposits develop into experimentally observed morphologies, given a set of macro-scopic charging conditions.

BASIC SCIENCE DIV S2: Electromagnetic Field Effects on Ceramic Processing: Fundamental Mechanisms and New Applications

Electromagnetic Field Effects on Ceramic ProcessingRoom: Nautilus BSession Chairs: Klaus van Benthem, University of California, Davis; Martha Mecartney

2:00 PM(EAM-BASIC-S2-007-2018) Flash sintering of ceramics: What is the role of the electric field? (Invited)R. I. Todd*1; E. Zapata-Solvas2; S. Falco3; M. Yoshida4; W. Ji5; Z. Fu6

1. University of Oxford, Department of Materials, United Kingdom2. Imperial College London, Centre for Nuclear Engineering. Dpt. of

Materials, United Kingdom3. University of Oxford, Department of Engineering Science, United Kingdom4. Gifu University, Japan5. Wuhan University of Technology, China6. Wuhan University of Technology, State Key Lab of Advanced

Technology for Materials Synthesis and Processing, China

“Flash sintering” refers to the rapid densification of ceramics with the aid of an electric field. Its main features are described and areas where consensus is developing are highlighted along with those

where more research is needed. It is shown that the thermal and electrical response characteristics can be explained well in terms of the negative temperature coefficient of resistivity of most ceramics. Attention is drawn to uncertainties concerning the electrical conduction of ceramics under these conditions. The second part of the presentation considers the rapid densification. The electric current leads to significant specimen heating but simple compari-sons with conventional heating do not explain the rapid sintering. It is also known that the application of electric fields to ceramics can influence microstructural development, but the relevance to flash sintering is not clear. Experiments are described in which 3YSZ powder compacts are heated and cooled with a temperature profile similar to that of flash sintering but without an electric field. The results show a significant acceleration in sintering compared with conventional sintering at the same temperature, but without the involvement of electricity. It is concluded that the rapid heating in flash sintering may be a major cause of the accelerated sintering. Possible explanations for this “ultra-fast firing” are discussed.

2:30 PM(EAM-BASIC-S2-001-2018) Thermal Runaway in Flash Spark Plasma and Microwave Sintering (Invited)E. A. Olevsky*1

1. San Diego State University, USA

An ultra-rapid process of flash hot pressing (or ultra-rapid spark plasma sintering) is developed based on the conducted theoretical analysis of the role of thermal runaway phenomena for material processing by flash sintering. The present study experimentally addresses the challenge of uncontrollable thermal conditions by the stabilization of the flash sintering process through the application of the external pressure. The effectiveness of the developed flash spark plasma sintering technique is demonstrated by the few seconds–long consolidation of SiC powder in an industrial spark plasma sintering device. Similarly to flash spark plasma sintering, the experimentally known thermal instability of microwave sintering is theoretically explained. It is shown that the sample location has a great impact on the temperature distribution and decreasing the sample size promotes temperature homogenization thereby assisting the overall sintering stabilization.

3:00 PM(EAM-BASIC-S2-003-2018) Flash Sintering of a Two- and Three-Phase Composites Constituted of Alumina, Spinel, and Yttria-Stabilized ZirconiaD. Kok*1; E. Sortino2; D. Yadav2; S. J. McCormack3; K. Tseng3; W. M. Kriven3; R. Raj2; M. Mecartney1

1. University of California, Irvine, Chemical Engineering and Material Science, USA

2. University of Colorado, Boulder, USA3. University of Illinois at Urbana-Champaign, USA

Two- and three-phase ceramic composites constituted from equal volume fractions of α-Al2O3, MgAl2O4 spinel and cubic 8 mol% Y2O3-stabilized ZrO2 (8YSZ) were flash-sintered under the influ-ence of DC electric fields from 250 to 700 V/cm. Experiments were conducted either by using a constant heating rate or isothermal experiments with increasing voltage. Flash sintering hold times of 6, 12, and 24 s were also used to determine their effect on the composites. During flash sintering of three-phase alumina, spinel and 8YSZ composites with high power densities and hold times of 24 s; alumina reacted with the spinel phase to form a high- alumina spinel solid solution, as identified by EDS. A decrease in the spinel lattice parameter as measured by XRD was also seen. In addi-tion, synchrotron in-situ XRD experiments demonstrate that the formation of high-alumina spinel occurs in less than 3 s along with the formation of a transient phase. The influence of 8YSZ content on flash behavior of the composite is also reported, with flash sintering of two-phase alumina and spinel achieved with fields of


Abstracts

650 V/cm. High-alumina spinel solid solution is again formed with flash sintering the two-phase alumina and spinel composite with a flash hold time of 24 s. A unique gradient grain size microstruc-ture is also observed, with larger grains formed in the center of the samples.

3:15 PM(EAM-BASIC-S2-008-2018) Impedance studies on flash sinteringY. Tsur*1; N. Shomrat2; S. Baltianski1

1. Technion - Israel Institute of Technology, Chemical Engineering, Israel2. Technion - Israel Institute of Technology, GTEP, Israel

Is flash sintering just a result of Joule heating? Joule heating in flash sintering depends on the sample resistance, which is linked to the charged defects concentration. To untie this link, we have made experiments on a model material.1 In SrTi1-xFexO3-d (STFO) system, point defect concentration can be pinned while the resistance is strongly influenced by the oxygen partial pressure (pO2). The needed onset temperature for flash sintering of STFO was identi-fied at different pO2. In another study, high compatibility of model and experimental results showed reduction of onset temperature with increasing doping. Ex-situ impedance measurements of green samples reveal an overlapping Nyquist plots close to the sample onset temperature. This indicates that the onset is determined by the green body resistance regardless how it has been achieved. Still, sintering is involved with moving ions and therefore detailed under-standing of the process following the flash instance is needed. The flash sintering setup is assembled in a dilatometer, utilizing its ability to measure shrinkage in-situ.2 AC measurements are performed before applying the field and after the sintering has been terminated. 1. N. Shomrat, E. Dor, S. Baltianski, and Y. Tsur, J. Eur. Ceram. Soc., 37, 179-188, (2017). 2. N. Shomrat, S. Baltianski, C.A. Randall, and Y. Tsur, J. Eur. Ceram. Soc., 35, 2209-2213, (2015)

4:00 PM(EAM-BASIC-S2-002-2018) Grain Boundary Core Structures Impacted by Electric Field Application in SrTiO3 Bicrystals (Invited)L. A. Hughes*1; K. van Benthem1


Application of processing techniques during manufacture of ceramic oxides leads to altered grain boundary networks. Changes in atomic and bonding configuration at the boundary core within these networks directly effects the physical properties of these materials. Ceramic oxides formed via sintering techniques with an applied electric field demonstrate enhanced consolidation with minimal grain growth and altered properties. Though application of an electric field is shown to modify oxygen concentration at the surface of single crystal strontium titanate (SrTiO3), how electric fields impact the densification process and thus grain boundary networks is currently under investigation. A fundamental study of grain boundary core structure as a function of electric field applica-tion is then needed. SrTiO3 bicrystals with twist angle of 40° along the <100> axis were fabricated with and without an electric field of 1 or 10 (e)3 V/m. Application of electric fields lead to distinct changes in atomic and bonding boundary core structure as well as electric properties, which were observed by scanning transmission electron microscopy (STEM) techniques, electron energy-loss spectroscopy (EELS), and impedance spectroscopy. These results reveal applica-tion of electric fields throughout bicrystal fabrication alter grain boundary thickness, oxygen vacancy concentration, and dielectric constant of SrTiO3.

4:30 PM(EAM-BASIC-S2-006-2018) High electric fields and currents in ceramics - Possible contributions to densification (Invited)G. A. Schneider*1

1. Hamburg University of Technology, Germany

The objective of this talk is to combine results from electric field distributions around voids and from electrical conductivities at high electric fields in order to estimate local heating rates in ceramics. Current-voltage measurements up 70 kV support the idea that space charge limited conduction (SCLC) is the dominating conduction mechanism at high electric fields. As a consequence electric field assisted sintering or breakdown models based on ohmic conduction must be critically regarded whether they can be applied. Fracture mechanics in ferroelectric ceramics developed analytical models of crack-like voids, which are applied to electric field assisted sintering of structural ceramics. The result reveals a dependency of the elec-tric field inside the ceramic on its permittivity. These two results, the SCLC model combined with the permittivity dependency are used to estimate local heating rates. Finally these results are discussed in comparison with published data.

5:00 PM(EAM-BASIC-S2-005-2018) Electric-current-controlled synthesis of BaTiO3 under a high DC electric field at elevated temperatures (Invited)H. Yoshida*1; Y. Nakagawa2; A. Uehashi2; T. Yamamoto2

1. National Institute for Materials Science (NIMS), Japan2. Nagoya University, Materials Design Innovation Engineering, Japan

Flash-sintering, where densification occurs almost immediately (typically <5 seconds) under high DC electric field, has attracted extensive attention as an innovative sintering technique since the first report in 2010. Flash-sintering has been demonstrated in various ceramics, and nearly full densities have been achieved at relatively low furnace temperatures for very short time. In the case of flash-sintering in BaTiO3, however, a surge of electric current through specimen accompanied with the occurrence of flash- sintering sometimes results in an inhomogeneous microstruc-ture including secondary phases due to discharging. We employed electric-current-controlled synthesis under a high DC field, where specimen current was set below the threshold value for the occur-rence of flash event, in order to avoid the discharging in BaTiO3. Uniform and fine-grained compacts were obtained without any secondary phases.; a relative density of 92 % was achieved under 100 V/cm, a limiting current of 72mA, and soaking at 1070°C for 3 h. Electron energy loss spectroscopy (EELS) revealed the genera-tion of excess oxygen vacancies near grain boundaries. The excess oxygen vacancies induced by application of DC electric fields were confirmed to retard the shrinkage rate in a final sintering stage.

5:30 PM(EAM-BASIC-S2-004-2018) Flash Sintering of Li-ion conducting lithium lanthanum titanate for Li-air batteriesV. L. Blair*2; S. V. Raju3; A. Fry3; M. Kornecki4; J. Wolfenstine1; R. E. Brennan1

1. US Army Research Laboratory, USA2. US Army Research Laboratory, Weapons and Materials Research

Directorate, USA3. ORAU, USA4. SURVICE Engineering, USA

The Army has a need for high energy density, lightweight batteries, which can reduce soldier load by up to 14 pounds. One potential method to reduce the load is to replace disposable, alkaline batteries with lithium (Li) air batteries, which weigh less due to high energy density and porous “air” cathode. Li-air battery performance is limited by the electrolytic membrane, which must have an extremely


Abstracts

high Li ion conductivity. Li0.33La0.55TiO3 (LLTO) is a promising electrolytic membrane material due to its high lattice conduc-tivity; however, the total conductivity of LLTO is lowered by its grain boundaries. Our previous work has shown that careful struc-tural modification and processing can improve the grain boundary conductivity. For the current work, we employed flash sintering, which occurs well below the conventional sintering temperature, to densify LLTO in an effort to reduce the amount of time at high temperature and avoid volatilization of the lithium. The effects of flash sintering on the microstructure and properties compared to conventional sintering will be presented.

5:45 PM(EAM-BASIC-S2-009-2018) Electric Fields Effects on Sintering and Grain Growth in MgAl2O4

W. Qin1; K. van Benthem*1


The application of electric fields can enable the accelerated consol-idation of materials during field assisted sintering. Although such techniques are already employed for the synthesis of a wide variety of microstructures with unique macroscopic properties, a funda-mental understanding of the atomic-scale mechanisms for grain boundary formation and subsequent migration in the presence of electrostatic potentials is mostly absent from the literature. This presentation reports on recent results on grain growth in nano-structured MgAl2O4 spinels as a function of applied electric field strength. Initial results demonstrate that applied electric fields can promote grain growth, but are most effective during the early stages of sintering, potentially implying to impact on surface diffusion.


Complex Oxide Heterostructures: Effect of Dimensionality and CorrelationRoom: Citrus ASession Chair: Anderson Janotti, University of Delaware

2:00 PM(EAM-ELEC-S1-005-2018) Probing electron-boson interactions in 2D electron liquids at the surface of transition metal oxides using ARPES (Invited)Z. Wang*1

1. Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, China

Two-dimensional electron liquids (2DELs) at the surfaces or inter-faces of transition-metal oxides emerge as an intriguing platform for investigating electron-boson interactions. Here I will present our recent angle resolved photoemission (ARPES) experiments on 2DELs at the surfaces of SrTiO3 and anatase TiO2 thin films. Employing photo-stimulated chemical surface doping we induce surface 2DELs with tunable carrier densities in a range of 1012 - 1014 cm-2. Subsequent in-situ ARPES measurements were performed to track the evolution of electron-phonon and electron-plasmon interactions. In the first part, we show the formation of 2D Fröhlich polarons in SrTiO3 2DELs due to polar electron-phonon interactions, and cross-over into Fermi liquid as the carrier density increases. In the second part, we show the transition from Fröhlich polarons into Holstein polarons, then plasmonic polaron in anatase TiO2 2DELs as the carrier density increases.

2:30 PM(EAM-ELEC-S1-009-2018) Resonant X-ray Reflectometry of Oxide HeterostructuresR. J. Green*1; G. Sawatzky1

1. University of British Columbia, Physics & Astronomy, Canada

Interfaces in oxide heterostructures exhibit a wide range of emergent phenomena, such as two dimensional electron gases (2DEGs), super-conductivity, and ferromagnetism between non-magnetic materials, many of which show great promise for electronics applications. However, while the emergent phenomena are readily apparent, obtaining electronic structure information specific to the nano-meter-scale buried interface region—in order to understand and further tune the emergent phenomena—is a difficult task. Here I will present our recent results of the study of oxide interface phenomena using resonant x-ray reflectometry (RXR), a new technique that we have shown provides interface and depth-sensitive information on electronic and magnetic structure with spatial resolution at the level of atomic planes. I will detail our results of extracting the high resolution depth profiles of charge density and orbital symmetry in a series of LaAlO3/SrTiO3 heterostructures. Further, I will show our results studying the interplay between electronic reconstruction and oxygen vacancies in trilayer systems such as LaAlO3/LaMnO3/SrTiO3, where we have shown that high electron mobilities can be realized through a unique modulation doping effect. RXR is able to disentangle the presence of oxygen vacancies at the upper interface and electronic reconstruction at the lower interface, yielding crucial insight into the mechanism for high mobilities.

2:45 PM(EAM-ELEC-S1-007-2018) Two-Dimensional Hole Gas at Oxide Interfaces (Invited)H. Lee*1; N. Campbell2; J. Lee3; T. J. Asel4; T. R. Paudel5; H. Zhou6; J. Lee1; B. Noesges4; L. J. Brillson4; S. Oh3; E. Y. Tsymbal5; M. Rzchowski2; C. Eom1


2. University of Wisconsin-Madison, Department of Physics, USA3. SungKyunKwan University, Republic of Korea4. Ohio State University, Department of Physics, USA5. University of Nebraska-Lincoln, Department of Physics and

Astronomy, USA6. Argonne National Lab, Advanced Photon Source 433E-095, USA

The discovery of two-dimensional electron gas (2DEG) at the LaAlO3/SrTiO3 interface has revealed a plethora of new proper-ties not present in conventional semiconductor heterostructures, becoming a focal point of novel device applications. Its counter-part, two-dimensional hole gas (2DHG), has long been expected to complement 2DEG and provide versatile functionalities. However, while 2DEG has been widely observed, the 2DHG has been elusive. Here, we report a highly-mobile 2DHG in epitaxially-grown SrTiO3/LaAlO3/SrTiO3 heterostructures. Using electrical transport measure-ments and in-line electron holography charge density mapping, we provide direct evidence of 2DHG coexisting with 2DEG at comple-mentary heterointerfaces in the same structure. First-principles calculations, coherent Bragg rod analysis, and depth-resolved cath-odoluminescence spectroscopy consistently support our finding that eliminating ionic point-defects is key to realize 2DHG. The coexis-tence of 2DEG and 2DHG in a single oxide heterostructure provides a platform for exciting new physics of confined electron-hole systems and for developing novel applications.


Abstracts

3:45 PM(EAM-ELEC-S1-008-2018) Probing Electronic Structure at the Unit Cell Level with Standing-Wave Photoemission (Invited)A. Gray*1

1. Temple University, Department of Physics, USA

Complex oxide superlattices provide a way to design, confine and control technologically-relevant physical properties with unit-cell precision. However, probing depth-dependent evolution of these engineered electronic, magnetic and structural phenomena can be a challenging task, requiring atomic resolution as well as element, orbital and spin selectivity. Over the past decade, standing-wave photoemission has evolved into a powerful and versatile nondestructive technique for investigating element-specific electronic, magnetic, and structural properties of such systems with unit-cell depth resolution. In this talk, I will discuss several promising future directions in this emergent field and present some of the most recent examples of applications of standing-wave techniques to the depth-resolved studies of buried interface phenomena.

4:15 PM(EAM-ELEC-S1-010-2018) FTIR study of SmNiO3 thin films: Elecron-phonon coupling, polarons, and a bad metalR. Jaramillo*1

1. Massachusetts Institute of Technology, USA

The rare-earth nickelates (RNiO3) feature an insulator-metal transi-tion that can be tuned from 0 to 600 K with chemical substitution, and an electronic phase diagram that is remarkably sensitive to epitaxial strain. As a late transition-metal oxide, understanding metal-oxygen orbital hybridization is key to understanding the physics of the nickelates. Here we discuss infrared spectroscopy and electronic transport measurements on epitaxial SmNiO3 thin films. We find evidence that electron-lattice coupling is the prin-ciple mechanism responsible for the insulator-metal transition. By measuring with fine temperature steps across TIM we track the evolu-tion of spectral features associated with the metallic and insulating phases. We will discuss our results in the context of proposals that RNiO3 are polaronic insulators. Furthermore, by varying oxygen content we observe how the metallic phase adjusts to an increase in disorder. Our results draw connections between electron-phonon coupling and bad metallicity observed in many correlated electron oxides.

4:30 PM(EAM-ELEC-S1-011-2018) Verification of oxygen exchange processes during resistive switching in SrTiO3 based memristive devicesT. Heisig*2; U. Gries1; C. Baeumer2; M. P. Müller1; D. Mueller2; R. A. De Souza1; R. Dittmann2

1. RWTH Aachen University, Institute of Physical Chemistry, Germany2. Forschungszentrum Juelich, Peter Gruenberg Institute, Germany

Resistive switching based on transition metal oxide memristive devices is suspected to be caused by nanoscale redox reactions and the electric field driven motion of oxygen anions. However, many models typically invoked to describe switching effects fail to clarify the frequently observed influence of the surrounding atmo-sphere. To investigate the role of oxygen during resistive switching, isotope labeling experiments in N2/H2

18O tracer gas atmosphere were combined with time-of-flight secondary ion mass spectrometry. We demonstrate that oxygen exchange processes take place during resistive switching in SrTiO3-based memristive devices. Specifically, we observed that during the RESET operation, voltage driven oxygen incorporation from the atmosphere into the SrTiO3 layer results in a high resistance state of the device. Furthermore, spatially resolved depth profiles were obtained, which allow predictions about the location and extent of the oxygen incorporation. Based on

these findings we conclude that resistive switching in this material system is caused by the exchange of oxygen between oxide and the surrounding atmosphere resulting in the reduction of SrTiO3 during SET and oxidation during the RESET operation.

4:45 PM(EAM-ELEC-S1-006-2018) Synchrotron light exposes buried physical phenomena: Low dimensional electronic system at Transition Metal Oxides (Invited)M. Radovic*1

1. Paul Scherrer Institut, Swiss Light Source, Switzerland

Transition Metal Oxides (TMOs) thanks to their iso-structural nature permits realization of heterostructures where novel unex-pected electronic properties take place. Engineering TMO surfaces and interfaces generates the potential for achieving new physical matter that radically differ from those of the constituent bulk mate-rials. Indeed, this is the case of oxide low dimensional electron gas (LDEgas), which is a key feature for extraordinary physical proper-ties such as interfacial superconductivity, surface magnetism, large tuneable spin-orbit coupling and topological states. In my talk, I will give an overview of Angle Resolved Photoemission Spectroscopy (ARPES) studies employed to understand fundamentally a nature of the low dimensional electron gas at surfaces of SrTiO3, TiO2-anatase and CaTiO3, and LaAlO3/SrTiO3 interface as well. Moreover, our studies establish different approaches to manipulate the properties of the two-dimensional electron gas at surfaces (and interfaces) of titanates.


Multiscale Structure-property Relationships IRoom: Magnolia A/BSession Chairs: Abhijit Pramanick, City University of Hong Kong; Julian Walker, Pennsylvania State University

2:00 PM(EAM-ELEC-S3-006-2018) Characterizing disordered ensembles of 2-D materials: Massively defective MnO2 nanosheet assemblies (Invited)S. T. Misture*1

1. Alfred University, MSE, USA

X-ray total scattering was teamed with Raman and X-ray spectros-copy and related tools to probe both the mesostructure and the atomic defects of MnO2 nanosheet assemblies, revealing a direct link between surface Mn Frenkel defects and pseudocapacitance. Nominally defect-free MnO2 nanosheets were reassembled into 3-D porous structures, followed by controlled reduction of some of the tetravalent Mn. As might be expected for a system of this complexity, nano and meso-scale disorder complicates the X-ray scattering data, making traditional approaches to quantification of defects impos-sible. X-ray PDF studies were used to quantify the Mn surface Frenkel defects by developing a new modeling approach for opti-mizing the fit of the model to the data. A refineable stacking model provides a mechanism to propagate the 2D sheet motif, where the critical feature of our new approach is the ability to refine a relatively small number of physically meaningful parameters for a massively defective atomic ensemble using only modest computing power. The approach is generally applicable to layered systems of any type, and we demonstrate that statistical modeling can be used to quantify the uncertainties in refined model parameters.


Abstracts

2:30 PM(EAM-ELEC-S3-007-2018) Study of the local structure and domain wall motion under application of electric fields of (1-x)BaZr0.2Ti0.8O3-xBa0.7Ca0.3TiO3

A. M. Manjón Sanz*2; C. M. Culbertson2; D. Hou1; J. L. Jones1; M. Dolgos2

1. North Carolina State University, Dept. of Materials Science & Engineering, USA


(1-x)BaZr0.2Ti0.8O3-xBa0.7Ca0.3TiO3, BZT-xBCT, is the first lead-free piezoelectric material with a piezoelectric coefficient high enough (620 pC/N) at its morphotropic phase boundary (MPB) at x=0.5 that has the potential to substitute the industry standard piezoceramic Pb(Zr1-xTix)O3. In this work, we are systematically investigating the domain wall motion and the local structure on compositions across the MPB for BZT-xBCT under an electric field (E). We want to help clarify aspects of the structure-property relationship in BZT-xBCT and gain an understanding of the local deviations from the average structure. In situ-E X-ray scattering and diffraction measurements were performed at the 11-ID-B beam line at Advanced Photon Source for compositions 0.40 ≤ x ≤ 0.60. The technique of pair distribution functions (PDFs), which provides the probabilities of atom-atom distances as a function of distance r, was used to study the local structural environments. Pawley fits were also performed to investigate the average structure and how the volume of the lattice changes as a function of E. We have found that both local and meso-scale structures of BZT-xBCT have respond to the E. For example, at the high-r region of directional PDFs, peaks shift to higher r in the direction parallel to the E, while they shift to lower r in the direction perpendicular to the E.

2:45 PM(EAM-ELEC-S3-008-2018) Coupling of emergent octahedral rotations to polarization in (K,Na)NbO3

I. Levin*1; V. Krayzman1

1. NIST, USA

Perovskite potassium sodium niobates, K1-xNaxNbO3, are promising lead-free piezoelectrics. Their dielectric and piezoelectric characteris-tics peak near x=0.5, but the reasons for such property enhancement remain unclear. We addressed this uncertainty by analyzing changes in the local and average structures across the x=0.5 composition, which have been determined using simultaneous Reverse Monte Carlo fitting of neutron and X-ray total-scattering data, potassium EXAFS, and diffuse-scattering patterns in electron diffraction. Within the A-sites, Na cations are found to be strongly off-centered along the polar axis as a result of oversized cube-octahedral cages determined by the larger K ions. These Na displacements promote off-centering of the neighboring Nb ions, so that the Curie tempera-ture and spontaneous polarization remain largely unchanged with increasing x, despite the shrinking octahedral volumes. The enhancement of the properties near x=0.5 is attributed to an abrupt increase in the magnitude and probability of the short-range ordered octahedral rotations, which resembles the pre-transition behavior. These rotations reduce the bond tension around Na and effectively soften the short Na-O bond along the polar axis – an effect that is proposed to facilitate reorientation of the polarization as external electric field is applied.

3:00 PM(EAM-ELEC-S3-009-2018) In situ synthesis and discovery of functional inorganic materials (Invited)D. P. Shoemaker*1


Exploratory materials chemistry seeks to uncover new compounds, which increasingly are formed under some non-traditional chem-ical potential. This deviation from thermally-driven solid-state reaction processes can be seen in our syntheses of semiconducting or magnetic materials. Sulfides, for example, can behave as oxides, with slow, thermally-driven diffusion reactions governed by phase diagrams. However their synthesis becomes more complex by melting, and confluence of these processes offers some opportuni-ties for synthetic control. In the case of the semiconductor Fe2SiS4, in situ diffraction reveals mechanisms (e.g. a peritectic onset of ternary compound formation) that bridge the solid state and melt scenarios. The ability to tune these material by metathesis reactions is also valuable. The defect-forming character and correlated-electron properties can be changed in situ, as in charge-doping superconduc-tors. We will discuss recent results from our lab on redox reactions in magnetic materials.

4:00 PM(EAM-ELEC-S3-010-2018) Domain Reorientation in Declamped {001} Pb(Zr0.3Ti0.7)O3 Thin FilmsL. M. Denis*1; G. Esteves2; J. Walker1; J. L. Jones2; S. Trolier-McKinstry1

1. Pennsylvania State University, Materials Science and Engineering, USA2. North Carolina State University, Materials Science and Engineering, USA

Extrinsic scaling effects in the piezoelectric and dielectric responses were studied in {001} textured PbZr0.3Ti0.7O3 (PZT 30/70) thin films of varying thicknesses (0.2 to 1 µm thick), dopant type (2% Nb and 1% Mn), and release state (clamped, 25% released, 50% released and 75% released from the substrate). The irreversible Rayleigh coefficient was thickness-dependent, indicating suppression of the extrinsic contributions to the relative permittivity in clamped films of thicknesses below 1.11 µm for either dopant type. Two factors contributed strongly to the thickness dependence: the presence of defect dipoles in the seed layer and substrate clamping effects. A correction of the data was applied to approximate the removal of the seed layer effect. Correction for the seed layer increased the irreversible contributions by up to 51% for Nb-doped films, with a smaller increase observed for Mn-doped films. As the films were partially declamped from the substrate, the irreversible contributions were further recovered by up to 23% in Nb-doped films. Moreover, the frequency dependence of the irreversible Rayleigh coefficient increases after correction (by up to 69%) and upon release (by up to 29%), indicating that both factors have a great influence on the pinning of slower moving irreversible domain walls.

4:15 PM(EAM-ELEC-S3-011-2018) In operando texture analysis of electroceramics at phase boundariesM. Hinterstein*1; K. Lee1; D. U. Seifert1; A. Studer2; M. Etter3; M. J. Hoffmann1

1. Karlsruhe Institute of Technology, Institute of Applied Materials, Germany2. Australian Nuclear Science and Technology Organization, Bragg

Institute, Australia3. Deutsches Elektronensynchrotron, Germany

Functional electroceramics are used in a broad range of applica-tions such as electromechanical devices, microelectronics, heating or cooling elements as well as current protection. Highest func-tional properties can be observed in the vicinity of phase boundaries. Dielectric and piezoelectric coefficients peak towards these regions. Therefore, compositions of highest technological interest, in many cases, exhibit phase coexistences. These phases usually are


Abstracts

highly correlated, complicating quantitative analysis. Additionally, uniaxial forces such as electric fields or mechanical stresses impose a preferred orientation. In the past years we developed a method that is able to describe all electromechanical effects that occur during operation of these materials. Based on crystallographic methods we are able to calculate the macroscopic behaviour on a model based on the atomic scale. The results also showed the origin of the rise in properties towards the phase boundaries. Based on experimental data and simulations we were able to develop a model for functional electroceramics in the vicinity of phase boundaries. This contribu-tion gives insight into the method and a range of applications.

4:30 PM(EAM-ELEC-S3-012-2018) Combined total scattering and first principles approach to understand structural disorder (Invited)S. M. Selbach*1; B. Jiang1; S. Skjærvø1; Q. Meier2; E. Bozin3; S. Billinge4; M. Feygenson5; N. Spaldin2; T. Grande1

1. NTNU Norwegian University of Science and Technology, Department og Materials Science and Engineering, Norway

2. ETH Zurich, Materials Theory, Switzerland3. Brookhaven National Laboratory, Condensed Matter Physics and

Materials Science Department, USA4. Columbia University, Department of Applied Physics and Applied

Mathematics, USA5. Forschungszentrum Juelich, Germany

We study structural disorder in the ferroelectric perovskite Bi0.5K0.5TiO3 (BKT) by synchrotron total scattering, and the improper ferroelectric hexagonal YMnO3 by spallation neutron total scattering. We combine small-box and large-box modelling of the experimental pair distribution functions (PDF) with density func-tional theory calculations (DFT) to derive models for the structural disorder in these crystalline compounds. For BKT we find that K+ and Bi3+ do not form long-range ordered structural configurations on the A-site. The structure of BKT can be described as multiple regions with large local polarization, which partly cancel each other on larger length scales. The structural phase transitions are diffuse without clear changes in the local structures. The ferroelectric phase transition of YMnO3 has been subject to debate, with a large range of reported TC values and controversy over the number of struc-tural transitions. Using high temperature spallation neutron total scattering we find that both the local and average structure display anomalies consistent with increasing fluctuations in the order parameter from ~800K to the TC of ~1250K. This local symmetry lowering persists into the paraelectric phase, constituting an uncon-ventional type of order-disorder transition.

5:00 PM(EAM-ELEC-S3-013-2018) Characterizing local atomic dynamics in real space and time (Invited)T. Egami*1

1. University of Tennessee, Materials Science and Engineering, USA

In non-crystalline materials and crystalline materials with strong disorder phonons have short lifetime, and are often localized. Thus it is not easy to characterize atomic dynamics and relate it to physical properties. I discuss how recent advances in scattering techniques and instrumentation made it possible to determine local atomic dynamics in real space and time, through the atomic dynamic pair-density function (DyPDF) and the van Hove function, which can be directly determined by elastic and inelastic x-ray and neutron scattering measurements. Examples include the local dynamics of relaxor ferroelectrics, liquid metals, superfluid helium and water.

5:30 PM(EAM-ELEC-S3-014-2018) The local structural origin of temperature-stable permittivity in BaTiO3 – Bi(Zn1/2Ti1/2)O3 ceramics (Invited)T. Usher*1; D. Hou2; J. S. Forrester3; N. Raengthon4; N. Triamnak5; D. Cann6; K. L. Page1; J. L. Jones2

1. Oak Ridge National Lab, Chemical and Engineering Materials, USA2. North Carolina State University, Materials Science and Engineering, USA3. University of Leeds, School of Chemical and Process Engineering,

United Kingdom4. Chulalongkorn University, Department of Materials Science, Thailand5. Silpakorn University, Department of Materials Science and Engineering,

Thailand6. Oregon State Univ, School of Mechanical, Industrial, and Manufacturing

Engineering, USA

Dielectrics based on BaTiO3 modified with Bi(M3+)O3 have been found to exhibit interesting and potentially useful dielectric and electronic properties. As the fraction of Bi(M3+)O3 increases to ~0.20, the dielectric permittivity typically becomes temperature indepen-dent over a wide range (0-200 °C). Many compositional variations of Bi(M3+)O3 induce this behavior, including M3+ = Mg1/2Ti1/2, Zn1/2Ti1/2, Y, Sc, and Mg2/3Nb1/3. In this work, we present detailed structural investigations using BaTiO3–xBi(Zn1/2Ti1/2)O3 as a model system to probe the short- and long-range structural origins of the anom-alous permittivity found in these materials. A combination of high resolution X-ray diffraction, neutron diffraction, and neutron pair distribution functions (PDFs) reveal that near 25 °C, compositions with x < 0.09 have a two-phase tetragonal and cubic structure. For x > 0.09, the structure appears pseudocubic by diffraction. However, analysis of neutron PDFs reveals the presence of local tetragonal distortions at length scales < 40 Å, indicating a short-range polar structure akin to the polar nanoregions in Pb-based relaxors. Temperature-dependent X-ray PDFs evidence the persistence of these local distortions to 225 °C, revealing the likely origin of the temperature-independent permittivity in BT-xBZT as local-scale distortions.

ELECTRONICS DIV S4: Agile Design of Electronic Materials: Aligned Computational and Experimental Approaches

Materials by Design: Computational/experimental Emerging Strategies for Searching, Designing, and Discovering New Electronic MaterialsRoom: Citrus BSession Chair: Venkatesh Botu, Corning Incorporated

2:00 PM(EAM-ELEC-S4-001-2018) Learning from data to guide experiments to find materials with targeted properties (Invited)T. Lookman*1

1. Los Alamos National Lab, Theoretical Division, USA

There has been much interest in accelerating the discovery of new materials. After reviewing how predictions from high throughput calculations compare with those obtained using experimental data, I will focus on how methods developed in the field of optimal experimental design can be used to guide experiments to find mate-rials with targeted properties in as few experiments as possible. As examples I will use the prediction of new perovskites and the search for Barium Titanate based piezoeelctrics with relativey large electrostrains.


Abstracts

2:30 PM(EAM-ELEC-S4-002-2018) High-Throughput Prediction of Two-Dimensional MX3 for Spintronics ApplicationsY. Zhang1; M. Ashton1; J. T. Paul*1; J. Gabriel1; D. Gluhovic1; R. G. Hennig1

1. University of Florida, Material Science and Engineering, USA

Two-dimensional (2D) materials can exhibit unique electrical and magnetic properties which may be useful in several fields, including optics, electrochemistry, and catalysis. However, many theoretically predicted 2D materials have not yet been synthesized due to a lack of thermodynamic stability. In this study, we determine the crystal structure and stability of 27 2D transition metal tri-chalcogenide MX3 (M = Cr, Mn, Fe, Mo, Tc, Ru, W, Re, Os; X = S, Se, Te) by using density-functional theory calculation. For each compound, we investigate 11 different 2D crystal structures that are based on the structures of known 2D MX3 materials. We predict that 6 of the 27 compounds (CrS3, CrSe3,CrTe3,MnS3,MnSe3,MnTe3) have suffi-ciently low formation energies for experimental synthesis. Using the HSE06 functional, we find that CrS3 and MnS3 are semiconduc-tors and the remaining compounds are metals. All but CrS3, CrSe3, CrTe3, MnSe3, and MnTe3 are ferromagnetic and exhibit large magnetic moments. These preliminary findings suggest that these materials might be useful components for nanoelectronic and spin-tronic devices.

2:45 PM(EAM-ELEC-S4-003-2018) Topological states and phonon couplings in electronic materials under large strains (Invited)Y. Chen*1

1. The University of Hong Kong, Department of Mechanical Engineering, Hong Kong

The IV-VI group binary compounds are promising for various applications such as thermoelectrics and photovoltaics. The rock-salt phases of IV-VI compounds SnTe and SnSe were found to exhibit topological states protected by crystal symmetries. In this work, the effects of hydrostatic strain on the topological states of IV-VI compounds have been thoroughly investigated combining evolutionary algorithms and density functional theory (DFT). Diamond anvil cell experiments have also been carried out to verify the theoretical predictions. On the other hand, the understanding of the strain effects on the phonon-phonon interactions in graphene is still incomplete. It was found in experiments that graphene ruptures at a nominal strain of 0.225 at ambient temperature, whereas a much smaller rupture strain was predicted from first-principles DFT calculations because of a soft phonon mode. In this work, anhar-monic force constants have been calculated from DFT for deeper insight into the phonon couplings in graphene under strains.

3:15 PM(EAM-ELEC-S4-004-2018) High-Temperature Quantum Anomalous Hall Effect on Post-Transition-Metal-Decorated GraphaneL. Zhang*1; C. Park1; M. Yoon1

1. Oak Ridge National Laboratory, Center for Nanophase Materials Science, USA

Quantum anomalous Hall (QAH) insulators are a highly promising class of materials for spintronic devices and quantum computa-tions because of their precise quantization nature, robust properties against defects, and relatively low energy consumption for opera-tion. To realize the QAH effect quantum spin Hall (QSH) insulators must be utilized, which requires transition metal doping or surface functionality control. Here, we propose a new way to introduce ferromagnetism to large-gap QSH insulators: we release the onsite magnetic momentum by increasing the lattice constants of stanene and germanene. If the lattice constant is increased to 9.5 Å, ab initio band structure calculations show that their spin–orbit coupling gaps are about 0.25 and 0.05 eV, respectively. Furthermore, the Curie

temperatures, calculated by the Monte Carlo method, are 780 and 420 K. Both results indicate that the room-temperature QAH effect can be realized on these systems. We also provide a possible exper-imental realization of this system on the 2 graphane substrate. Our calculations predict the first room-temperature QAH insulator in the realistic materials system. Funding: L.Z. was partly supported by the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory. Computing resources were provided by the National Energy Research Scientific Computing Center.

4:00 PM(EAM-ELEC-S4-005-2018) Autonomous phase mapping for the lab and the beamline (Invited)A. Kusne*1; B. DeCost1; J. Hattrick-Simpers1; I. Takeuchi2

1. National Institute of Standards and Technology, USA2. University of Maryland, USA

The last few decades have seen significant advancements in mate-rials research tools, allowing researchers to rapidly synthesis and characterize large numbers of samples - a major step toward high-throughput materials discovery. Machine learning has been tasked to aid in converting the collected materials property data into actionable knowledge, and more recently it has been used to assist in experiment design. In this talk we demonstrate the next step in machine learning for materials research - an autonomous materials measurement system. The software system controls X-ray diffraction measurement systems both in the lab and at the beamline to identify phase maps from composition spreads with a minimum number of measurements. The algorithm also capitalizes on prior knowledge in the form of physics theory and external databases, both theory-based and experiment-based, to more rapidly hone in on the optimal results. Materials of interest include Fe-Ga-Pd, TiO2-SnO2-ZnO, and Mn-Ni-Ge.

4:30 PM(EAM-ELEC-S4-006-2018) Atomic and Electronic Structure in Amorphous InGaZnO4

D. Fast*1


InGaZnO4 (IGZO) is an emerging oxide semiconductor that has received increasing interest for display technologies in recent years. However, there is still much debate over the structural roots of the electronic properties in this material, both in terms of defects and the explicit roles of the various cations. In order to refine future iter-ations of this material and similar amorphous oxide semiconductors, a deeper understanding of the structure-property relationships in IGZO is necessary. This work utilizes both ab-initio work and x-ray total scattering experiments to characterize the structural motifs of IGZO. Initial structures are generated using a molecular dynamics melt-quench procedure and then refined with reverse Monte Carlo techniques to match the total scattering data. These models are analyzed in order to elucidate the bonding and coordination envi-ronments present in this amorphous oxide. The density of states is calculated using these refined structures to pinpoint the structural origins of the unique electronic states that give rise to the desirable electronic properties of this material. Overall, this work is intended to define a methodology for the study of structure-property relation-ships in amorphous oxides using IGZO as a commercially relevant test case.


Abstracts

4:45 PM(EAM-ELEC-S4-007-2018) Prediction of hybrid organic-inorganic elpasolite formation via convex hull phase diagram analysisS. Xie*1; M. Sexton1; J. Xue1; S. R. Phillpot1; R. G. Hennig1

1. University of Florida, Materials Science and Engineering, USA

Hybrid-perovskite materials have excellent photovoltaic proper-ties and are inexpensive to synthesize, providing a promising route towards meeting the ever-growing energy demand of the world. The widespread use of the well-studied CH3NH3PbI3 perovskite is hindered by instability and the toxicity of its lead component. We explore the thermodynamic stability of “double” perovskite structures with mixed metal ions [(CH3NH3)2BB’X6] to iden-tify new lead-free materials suitable for photovoltaic applications. Specifically, we construct the four-dimensional phase diagram and the convex hull of energy vs. composition for each chemical system using density functional theory. We show that the lowest-en-ergy structures and reaction energies identified by these convex hulls compare favorably with experimental synthesis results, and predict the formation of double perovskites more accurately than Goldschmidt’s tolerance factor.

5:00 PM(EAM-ELEC-S4-008-2018) Computational Discovery of Candidate Replacements for Pb in orthorhombic CH3NH3PbI3 for solar cell applicationsJ. J. Gabriel*1; S. Xie1; K. Choudhary2; M. Sexton1; S. R. Phillpot1; J. Xue1; R. G. Hennig1

1. University of Florida, Materials Science and Engineering, USA2. National Institute of Standards and Teechnology, USA

Due to the toxicity of lead, there is a compelling need to replace lead in the organic-inorganic hybrid perovskite CH3NH3PbI3 a high- performance photovoltaic material. We computationally investigate 28 candidate materials by substituting Pb with elements exhibiting a +2 oxidation state: from Group IVA: Si, Ge, and Sn; from the alkali earth elements: Be to Ba; from the transition metals: Ti to Zn, Pd to Cd, Pt to Hg and from lanthanides: Ce, Sm, Nd, Yb, Tm. We screen these 28 materials based on their Goldschmidt tolerance factor and then use density functional theory calculations with the generalized gradient approximation (GGA) functional of PBEsol to identify candidate materials based on their band gap. We choose a band gap criterion of 0.1 to 3.2 eV which corresponds to the spectrum of solar radiation and also accounting for the underestimation of the bandgap in the PBEsol approximation. For the materials which pass these first two steps of screening, we use the recently developed meta-GGA functional SCAN and the hybrid functional HSE06 to characterize their band gap, optical absorption spectrum, and effec-tive mass tensor and hence identify candidate replacements for Pb in CH3NH3PbI3. We conclude that several materials from Group IVA, the alkali earth metals, and transition elements are promising replacements of Pb.


Cation Conducting Ceramics for Energy StorageRoom: Cypress A/BSession Chairs: Hui Xiong, Boise State University; Erik Spoerke, Sandia National Laboratories

2:00 PM(EAM-ELEC-S5-001-2018) Safe, High-Energy-Density, Solid-State Li Batteries (Invited)E. D. Wachsman*1

1. University of Maryland, USA

We have developed transformational, and intrinsically safe, all-sol-id-state Li-ion batteries (SSLiBs), by incorporating high conductivity garnet-type solid Li-ion electrolytes into tailored tri-layer micro-structures, by low-cost solid oxide fuel cell (SOFC) fabrication techniques to form electrode supported dense thin-film (~10µm) solid-state electrolytes. The microstrucurally tailored porous garnet scaffold support increases electrode/electrolyte interfacial area, overcoming the high impedance typical of planar geometry SSLiBs resulting in an area specific resistance (ASR) of only ~2 Ωcm-2 at room temperature using Li-metal/garnet/Li-metal symmetric cells. The unique garnet scaffold/electrolyte/scaffold structure further allows for charge/discharge of the Li-metal anode and cathode scaf-folds by pore-filling, thus providing high depth of discharge ability without mechanical cycling fatigue seen with typical electrodes. Moreover, these scalable multilayer ceramic fabrication techniques, without need for dry rooms or vacuum equipment, provide for dramatically reduced manufacturing cost. Fabrication of supported dense thin-film garnet electrolytes, their ability to cycle Li-metal at high current densities with no dendrite formation, and results for Li-metal anode/garnet-electrolyte based batteries with a number of different cathode chemistries will be presented.

2:30 PM(EAM-ELEC-S5-002-2018) Strain Effects on Ionic Transport in Perovskite OxidesR. Gao*1; A. Jain2; S. Pandya1; Y. Dong3; L. Dedon1; S. Saremi1; A. Luo1; H. Zhou3; T. Chen4; N. H. Perry4; D. Trinkle2; L. W. Martin1



3. Argonne National Lab, X-ray Science Division, Advanced Photon Source, USA

4. Kyushu University, International Institute for Carbon-Neutral Energy Research (WPI-I2CNER), Japan

Epitaxial strain has long been suggested as a promising strategy to enhance oxygen ion conduction in perovskite oxides. However, there has been limited understanding of the correlation between oxygen ion diffusion and strain-induced structural changes in strongly- correlated systems. In this work, epitaxial strain (from -1.1% to +0.79%) is applied by growing 100 nm model perovskite oxygen ion conducting system La0.9Sr0.1Ga0.9Mg0.05O3-δ (LSGM) thin films on various perovskite substrates with pulsed-laser deposition. Both laboratory and synchrotron X-ray diffraction studies reveal that the LSGM unit cell volume monotonically increases upon transitioning from compressive to tensile strain, while the octahedral rotation is strongest at zero strain but is largely quenched at both compressive and tensile strains. Further electrical studies revealed that the ionic conduction increases by one order of magnitude from compressive to tensile strain, while the ionic migration barriers under different strain states were determined to be 0.74 eV (-1.10%), 0.74 eV (-1.05%), 0.60 eV (+0.1%), and 0.75 eV (+0.79%), respectively. Our


Abstracts

results reveal that, strain can impose a dramatic change on ionic conductivity and migration barriers in perovskite materials, which are likely correlated to both unit cell volume and octahedral rotation effects. It is further suggested that larger unit cell and stronger octa-hedral rotations are preferred.

2:45 PM(EAM-ELEC-S5-003-2018) Fabrication and excellent Li+ conductivity of a novel NASICON-type solid electrolyteS. Kumar*1; T. Pareek1; S. Dwivedi1; A. Yadav1; A. Verma1; S. Sen1

1. Indian Institute of Technology Indore, Metallurgy Engineering and Materials Science, India

Safety issues associated with the high flammability and volatility of organic electrolytes used in commercial rechargeable lithium-ion batteries has led to significant attention to ceramic-based solid electrolytes. In this work, LiZrSn(PO4)3 (LZSP) ceramics were fabri-cated via a sol-gel route. Rietveld refinement of synchrotron X-ray diffraction data confirmed the room temperature crystal structure of LiZrSn(PO4)3 as rhombohedral (R-3c space group). The Zr 3d, Sn 3d, P 2p, and O 1s, core level X-ray photoelectron spectra (XPS) associated with different valence states on the LZSP sample were deconvoluted. Surface morphology, densification, and the ionic conductivity of ceramics sintered at various temperatures were investigated. LZSP ceramics sintered at 1273 K exhibited an excel-lent room temperature ionic conductivity of about 10-4 Scm-1 and associated activation energy ~ 0.39 eV in the temperature range of 300 – 500 K. DC polarization study confirmed the conductivity of LZSP ceramics as predominantly ionic. Distinct relaxations observed in dielectric and modulus formalisms and the temperature depen-dence thereof are also discussed.

3:00 PM(EAM-ELEC-S5-004-2018) Understanding Electrochemical and Structural Behaviors of Irradiation Induced Defects in TiO2

K. A. Smith*1; A. Savva1; Y. Wang2; D. Su3; S. Hwang3; J. Wharry4; H. Xiong1

1. Boise State University, Material Science and Engineering, USA2. Los Alamos National Laboratory, Ion Beam Materials Laboratory, USA3. Brookhaven National Laboratory, Center for Functional Nanomaterials,

USA4. Purdue University, Nuclear Engineering, USA

Ion irradiation is known to produce high concentration of defects in materials. Recent studies have indicated enhanced electrochem-ical charge storage in electrodes used for rechargeable metal-ion batteries that contain intentional structural defects. In this study, we investigate the fundamental effects of irradiation on single crystal and nanostructured TiO2 to understand how it may alter the oxide structure, which in turn affects its electrochemical charge storage properties when used as an electrode in Li-ion batteries. Specifically, the influence of irradiation on the structural and electrochem-ical behaviors of both amorphous and anatase polycrystalline TiO2 nanotubes, as well as single crystal rutile substrates will be discussed.

3:15 PM(EAM-ELEC-S5-005-2018) Compositional Changes of Chemically Exfoliated Lithium Cobalt OxideK. G. Pachuta*1; A. Sehirlioglu1; E. Pentzer2

1. Case Western Reserve University, Materials Science and Engineering, USA2. Case Western Reserve University, Chemistry, USA

Layered transition metal oxides have a variety of applications due to their intrinsic properties ranging from metallic to wide-gap insulating. When isolating into atomic layers, these expansive properties can be utilized along with quantum confinement of two- dimensional structures for various applications such as energy generation and storage, catalysis, sensing, optoelectronics, and more. Layered metal oxide structures, such as lithium cobalt oxide (LiCoO2, LCO), can be exfoliated into atomically thin layers by

weakening its interlayer electrostatic forces. Exfoliation of LCO is typically completed in a two-step, wet-chemical, ionic intercala-tion and replacement method. This presentation is focused on the quantification of defects and off-stoichiometry during the first step of the reaction which uses acid to replace Li-ions with protons. This includes dissolution (28%), vacancies (Li-site 39%, Co-site 22%, O-site 18%), and a change in Co oxidation state (3.46), coordination, and surface ligands, and will be covered in detail. Defect generation will also be discussed in terms of processing parameters such as acid molarity, treatment duration, and loading content. The presence of atomically thin CoO2 nanosheets, as confirmed by AFM and TEM characterization, will be shown and is realized in the second step of the reaction using a bulky amine to expand the interlayer spacing and promote exfoliation.

Mechanisms for Ion TransportRoom: Cypress A/BSession Chairs: Hui Xiong, Boise State University; Miaofang Chi, Oak Ridge National Lab

4:00 PM(EAM-ELEC-S5-006-2018) Towards New All Solid State Li and Na Batteries: Glass the Enabling Material (Invited)S. W. Martin*1

1. Iowa State University, Materials Science & Engineering, USA

Li batteries are fire and explosion hazards. They also operate at 10 times less energy density than theoretically possible. The first of these problems is caused by the flammable liquid electrolyte used in their construction that can spontaneously ignite or explode if lithium ion batteries are charged incorrectly, stored in hot conditions, or discharged too rapidly. The second of these problems is caused by the fact that to give these batteries the little safety they do have, they must use graphitic carbon that reduces the amount of lithium that can be stored to 10% of the theoretical value. In spite of these two critical problems, lithium batteries remain about the only choice manufacturers have to store electrical energy for portable electronics and automobile propulsion. In our research ISU, we are working to solve these two critical problems and at the same time make lithium and sodium batteries that are cheaper and can be charged much faster. The core break through that has led to this possibility is the discovery of new solid electrolytes that conduct lithium and sodium ions through the battery more safely and faster than the flammable liquid electrolytes used to day. In this talk, I will describe our recent research that has led to the break through achievements of our research group in this area.

4:30 PM(EAM-ELEC-S5-007-2018) Microscopic Insights into Conductivity and Stability of Solid Electrolyte Interface (Invited)M. Chi*1; J. Sakamoto2; N. Dudney1

1. Oak Ridge National Lab, Materials Science and Technology Division, USA

2. University of Michigan, USA

New solid electrolyte materials were developed recently that demon-strated high conductivity. However, unexpectedly high resistivity from electrolyte-lithium interfaces is often observed and became one of the major limitations in realizing the practical application of these materials. Experimentally probing these interfaces is challenging and the exact origins are under debate. Here, in situ scanning transmission electron microscopy (STEM) and electron energy loss spectroscopy are used to study the interfaces between lithium metal and solid electrolytes, including Al-Li7La3Zr2O12 (LLZO) and LIPON. At the LLZO-lithium interface, the formation of an ultra-thin, self-limiting layer was discovered, which serves as a passivation layer that stabilizes the interface. An obvious chemical reaction accompanied with volume expansion occurs immediately upon the


Abstracts

contact of LIPON and Li, forming an interphase layer that is mainly composed of binary oxides. The nature and the dynamics of this interphase layer will be discussed in the presentation. While chem-ical reactions and phase transformations can be well characterized by STEM, a grant challenge in studying these interfaces is to probe local ion diffusivity. A new TEM technique that can potentially map local ion diffusion will be introduced.

5:00 PM(EAM-ELEC-S5-008-2018) SIMS Study of Oxygen Diffusion in Monoclinic HfO2

M. P. Müller*1; R. A. De Souza1

1. RWTH Aachen University, Institute for Physical Chemistry, Germany

Research on hafnia and zirconia has received a boost in the last two decades, mainly because of their electrical properties. As materials with high dielectric permittance and a wide band-gap, they can replace SiO2 in metal-oxide semiconductor devices. A key part of producing such devices is the annealing process, involving defect and oxygen migration through the device. While oxygen diffusion in solid solutions based on ZrO2 has been investigated in great detail, diffusion in monoclinic HfO2 has been largely neglected. The diffu-sion of oxygen in dense ceramics of monoclinic HfO2 was studied by means of (18O/16O) isotope exchange annealing and subsequent determination of the isotope depth profiles by Secondary Ion Mass Spectrometry (SIMS). Anneals were performed in the tempera-ture range 573 ≤ T [K] ≤ 973 at an oxygen partial pressure of pO2 = 200 mbar. All measured isotope profiles exhibited two features: the first feature, closer to the surface, was attributed to slow oxygen diffusion in an impurity silicate phase; the second feature, deeper in the sample, was attributed to oxygen diffusion in a homogeneous bulk phase. The activation enthalpy of oxygen tracer diffusion in bulk HfO2 was found to be ΔHD*≈ 0.5 eV.

5:15 PM(EAM-ELEC-S5-009-2018) Electrical conductivity and microstructure in sintered Li4Ti5O12 anodes for structural batteriesW. Huddleston*1; F. Dynys2; A. Sehirlioglu1

1. Case Western Reserve University, Department of Materials Science and Engineering, USA

2. NASA Glenn Research Center, USA

In this study, all-solid-state structural lithium-ion batteries, a type of load bearing electrochemical energy storage that provides systems-level weight savings, is being pursued for the realization of inherently safe next generation hybrid-electric and all-electric green aerospace propulsion systems. To improve electrical conductivity of strain free but insulating Li4Ti5O12 anode material, this study explored doping to increase electronic charge carrier density and processing of composites with addition of metallic current collec-tors. Processing with Ta2O5 dopant and additions of metallic copper, nickel, and chromium were explored. These modifications were characterized in relationship to the densification and microstruc-tural development of sintered Li4Ti5O12 across processing variables to achieve multifunctional design goals of high fracture strength and electronic conductivity. AC impedance spectroscopy measurements showed significant improvements in decreasing electrical resistivity of 1x107Ωcm for the unmodified material down to 1.2x103Ωcm for forming gas treatment, 2.4x102Ωcm for Ta2O5 doping, 6x102Ωcm and 43 Ωcm for copper and nickel addition as a composite, respec-tively. Doping with Ta2O5 promoted grain growth and an observed CTE mismatch between current collection phases and ceramic matrix resulted in suppressed densification with addition of copper and nickel.

5:30 PM(EAM-ELEC-S5-010-2018) Effect of thickness on epitaxial growth and transport properties of solid electrolyte LiLaTiO3 thin film fabricated by pulsed laser depositionE. Farghadany*1; A. Sehirlioglu1

1. Case Western Reserve University, Materials Science and Engineering, USA

All-solid-state batteries could offer significant advantages compared to the conventional Li-ion batteries, such as improved safety, absence of leakage and shorting related issues. Among the oxide solid electrolytes, perovskite-based Li3xLa2/3_xTiO3 (LLTO) has been extensively studied due to its high lithium ion conductivity at room temperature (max at 10-3 S.cm-1 for x=0.11). However, LLTO has a number of issues as a solid electrolyte, such as instability against Li metal and reduced ionic conductivity due to the grain boundaries. Epitaxialy oriented LLTO film, would allow Li to move anisotrop-ically and it would also minimize the adverse contribution of grain boundary to total conduction. In the present study, we have success-fully grown single crystal LLTO films on SrTiO3 substrates. The growth quality is monitored with RHEED as a function of deposition parameters. The quality of interface, surface of the film, and epitaxy as well as compositional changes will be presented following analysis of high resolution XRD, X-ray Reflectivity and AFM techniques. In order to enhance the conductance of the films, also growth of super-lattice structures of LLTO/STO will be presented.


Strain EffectRoom: Orange DSession Chair: Rui Wu, University of Cambridge

2:00 PM(EAM-ELEC-S8-014-2018) Strain control of oxygen exchange kinetics in Ruddlesden-Popper oxides (Invited)H. Lee*1


Functional defects, such as oxygen vacancies, in perovskite oxides play a central role in the performance of quantum materials. We have explored strain-mediated oxygen vacancy formation and migration in strontium cobaltite “oxygen sponges” (SrCoO3−δ) and Ruddlesden-Popper phase Sr-doped La2CuO4. From these materials, we have found unanimously that the oxygen vacancy activation and oxygen ion conduction are very sensitive to the sign and magni-tude of epitaxial strain. Density functional theory calculations for SrCoO3−δ confirm that the activation energy barrier for oxygen diffu-sion can be reduced by ~30% under only 2% tensile strain, whereas it is increased for compressive strain. In case of doped La2CuO4, the oxygen non-stoichiometry commonly reported for these strained cuprates is mediated by the strain-modified surface exchange kinetics, rather than reduced thermodynamic oxygen formation energies for one strain state versus another. Remarkably, tensile-strained LSCO shows nearly an order of magnitude faster oxygen exchange rate than a compressively-strained film, revealing a strong contrast in the time scales required to modify oxygen stoichiom-etry. In this talk, I will present approaches to strain engineering in epitaxial multivalent transition metal oxides synthesized by pulsed laser epitaxy in order to control the oxygen vacancy concentration and improve oxygen ion conduction by epitaxial strain.


Abstracts

2:30 PM(EAM-ELEC-S8-015-2018) Enhanced magnetic properties in microstructured manganites (Invited)A. Biswas*1; H. Jeen2; I. Kwak1; D. Grant1

1. University of Florida, Physics, USA2. Pusan National University, Physics, Republic of Korea

Hole-doped manganites such as La1-xSrxMnO3 (LSMO) are prom-ising candidate materials for magnetic memories, logic devices, and sensors since they possess high spin polarization and display colossal magnetoresistance. However, these materials have low Curie temperatures (less than 400 K) and magnetic anisotropy (~ 104 erg/cm3) which has hindered any realistic applications. In this presentation, I will show that a small amount of anisotropic strain is sufficient to produce large uniaxial magnetic anisot-ropy (~106 erg/cm3) due to phase competition in the manganite (La1-yPry)1-xCaxMnO3 (LPCMO). In thin films of LPCMO grown on (110) NdGaO3 using pulsed laser deposition, the combined effect of magnetic anisotropy and phase competition leads to a single domain to multidomain transition in this chemically homogeneous material. When these thin films are patterned into microstructure arrays, the magnetic coercive field is enhanced by almost a factor of five. It may also be possible to tune the magnetic coercive field of these micro-structures with an electric field.

3:00 PM(EAM-ELEC-S8-016-2018) Nanoscale Strain and Doping Modulation of Magnetic Anisotropy in (La,Sr)MnO3 Nanostructures and Heterostructures (Invited)X. Hong*1

1. University of Nebraska-Lincoln, Physics and Astronomy, USA

Originating from spin-orbit coupling, the magnetocrystalline anisot-ropy (MCA) in strongly correlated oxides is highly susceptible to the change of orbital occupancy, which is closely entangled with the charge and lattice degrees of freedom. In this talk, I will discuss our recent efforts in understanding and controlling MCA in epitaxial (La,Sr)MnO3 (LSMO) nanostructures and hetero-interfaces. By creating nanoscale periodic depth modulation in ultrathin LSMO films, we have achieved a 50-fold enhancement of the MCA energy density, which is attributed to a non-equilibrium strain distribu-tion established in the nanostructures. We have also modulated MCA in Pb(Zr,Ti)O3/LSMO heterostructures through polarization switching, and compared the results with the doping effect predicted by first-principles density functional calculations. Our work points to effective routes for functional design of the magnetic properties of strongly correlated oxides, paving the path for their application in nanoelectronic and spintronic applications.

FerroelectricityRoom: Orange DSession Chair: Robert Green, University of Saskatchewan

4:00 PM(EAM-ELEC-S8-012-2018) Phase Coexistence in Multiferroic BiFeO3-based Superlattices (Invited)J. Mundy*1

1. Harvard University, USA

Advances in thin-film deposition have enabled materials to be ratio-nally designed at the atomic-scale to stabilize emergent phenomena. In particular, ferroelectric and ferromagnetic phases can be strongly modified in the ultra-thin film geometry due to applied strain from the substrate, size effects of the material and electronic charges induced at the interfaces. Here we construct superlattices based on the prototypical multiferroic material, BiFeO3, and an adja-cent dielectric layer. The strong depolarizing fields at the interface

modifies the strongly crystallographic structure of the BiFeO3 layer, driving the material from the ferroelectric ground state into two distinct antiferroelectric states, including one not observed previ-ously in (doped) BiFeO3 films. Moreover, neutron diffraction results demonstrate an unusual magnetic field dependence of the expected G-type antiferromagnetic structure coincident with this antiferro-electric instability. Combined our results demonstrate the ability of interfacial electric fields to modify the crystal symmetry and in turn the electronic and magnetic properties of multiferroic materials.

4:30 PM(EAM-ELEC-S8-018-2018) Room-temperature relaxor ferroelectricity and photovoltaic effects in SnTiO3/Si thin film heterostructures (Invited)S. Hong*3; R. Agarwal4; Y. Sharma1; S. Chang5; C. Sohn1; K. Pitike2; S. Nakhmanson2; C. Takoudis5; H. Lee1; J. F. Scott6; R. Katiyar4

1. Oak Ridge National Lab, Materials Science and Technology Division, USA

2. University of Connecticut, Materials Science and Engineering, USA3. Korea Advanced Institute of Science and Engineering (KAIST), Materials

Science and Engineering, Republic of Korea4. University of Puerto-Rico, Department of Physics and Institute for

Functional Nanomaterials, USA5. University of Illinois at Chicago, Department of Chemical Engineering,

USA6. University of St. Andrews, School of Physics and Astronomy,

United Kingdom

Tin titanate (SnTiO3) has been notoriously impossible to prepare as a thin-film ferroelectric, probably because high-temperature annealing converts much of the Sn+2 to Sn+4. Here we show two things: First, that perovskite phase SnTiO3 can be prepared by ALD directly onto p-type Si substrates; and second, that these films exhibit ferroelectric switching at room temperature, with the p-type Si acting as electrodes. These films showed well-saturated, square and repeatable hysteresis loops of 3.1 µC/cm2 remnant polarization at room temperature, as detected by out-of-plane polarization versus electric field (P-E) and field cycling measurements. This is a new lead-free room-temperature ferroelectric oxide of potential device application.

5:00 PM(EAM-ELEC-S8-019-2018) Permanent ferroelectric retention of BiFeO3 mesocrystal in a BiFeO3-CoFe2O4 nanocomposite (Invited)Q. He*1

1. Durham University, Physics, United Kingdom

Non-volatile electronic devices based on magnetoelectric multifer-roics have triggered new possibilities of outperforming conventional devices for applications. However, ferroelectric reliability issues, such as imprint, retention and fatigue, must be solved before the realization of practical devices. In this talk, I will show you a model system, a self-assembled BiFeO3 mesocrystal embedded in a CoFe2O4 matrix, to utilize the elastic energy as a key parameter to solve the ferroelectric retention problem of the multiferroic BiFeO3, suggesting a new approach to overcome the failure of ferroelectric retention. The intimate contact between the mesocrystal and matrix material provides a strong structural coupling. This elastic energy term can be exploited to improve the ferroelectric retention since the ferroelectric switching of BiFeO3 typically involves an elastic deformation. The achievement of an improvement in retention to a great extent in BiFeO3 can open up a new avenue for ferroelec-tric retention studies and the possible applications in electric-field controllable spintronic memory and logic devices.


Abstracts

5:30 PM(EAM-ELEC-S8-020-2018) Complication of ferroelectricity to enhance electrostrain (Invited)S. Choi*1

1. Pohang University of Science and Technology(POSTECH), Materials Science & Engineering, Republic of Korea

Properties of new functional materials strongly depend on the composition and atomic structure down to the level of single atoms, and thus characterization at the atomic scale has been a key tech-nology in materials science. We previously visualized that the polarization was largely enhanced in the polar core – nonpolar shell model wherein electric field-induced strain was also improved. Therefore, the propagation of polarization can be promoted by the mixture of polar and nonpolar phases; or by using the nano-composite materials embedding the ferroelectric nanoparticles, each of which exhibits the flexible single domain. As polarization configuration at the interface between polar and nonpolar phases in nanocomposite have a completely behave different with that of interior domains, peculiar types of polarization configuration, such as nanoscale rotational vortices, can be dominant in the nano-metric dimension, where the large strain effect should be necessarily considered. We utilize atomic scale STEM to understand the local polarization giving rise to atomic displacement and also in-situ TEM technique to dynamically observe the polarization by biasing the electric field or mechanical stress. Herein we emphasize that the coherent interface between polar and non-polar phases is a key factor for understanding the enhanced piezoelectric properties of the composite.


Characterization of Materials I: Crystal StructureRoom: Orange CSession Chairs: Jacob Jones, North Carolina State University; Zhongming Fan, Iowa State University

2:00 PM(EAM-ELEC-S13-024-2018) Polarization rotation and field-induced phase transitions in ferroelectric ceramics (Invited)J. L. Jones*1; D. Hou1; C. Zhao1

1. North Carolina State University, Dept. of Materials Science & Engineering, USA

The rotation of spontaneous polarization (Ps) within ferroelectrics can lead to extraordinary piezoelectric properties and is associated with the monoclinic (M) cell, in which Ps can potentially rotate with the lattice parameter β. This possibility of polarization rotation has been known since the work of Park and Shrout (1997) and then explained theoretically by Fu and Cohen (2000). While significant work on polarization rotation in single crystals has occurred since, there are fewer studies on the possible existence of polarization rota-tion in ferroelectric ceramics. One reason for this may be that sharp inflections in responses are not observed from ceramics, possibly due to grain-orientation averaging. Here, we report in situ X-ray scattering studies of (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 (PMN-xPT) and Pb(Zr,Ti)O3 ferroelectric ceramics during application of fields. Both Bragg diffraction and Pair Distribution Functions (PDFs) are analyzed. Both materials show polarization rotation. In PMN-30PT, e.g., field-induced phase transitions occur from M (space group

Cm) to orthorhombic Amm2 to M (Pm) and, finally, to two-phase M+tetragonal (Pm+P4mm). Polarization rotation is clearly captured in both Cm and Pm monoclinic phases and can be an important mechanism in ferroelectric ceramics. We will acknowledge many groups that collaborated on this topic during the talk.

2:30 PM(EAM-ELEC-S13-025-2018) Correlating local chemistry with local structure in relaxor ferroelectricsM. J. Cabral*1; S. Zhang2; B. Reich3; E. C. Dickey1; J. LeBeau1

1. North Carolina State University, Materials Science and Engineering, USA2. University of Wollongong, Institute for Superconducting & Electronic

Materials, Australia3. North Carolina State University, Department of Statistics, USA

Relaxor ferroelectrics are an important class of materials whose properties are driven by nanoscale polar order. Despite decades of research, the governing mechanism that results in relaxor ferroelec-tric behavior is still unknown to researchers. Although it is believed that local competition between composition/charge ordering contributes to the formation of nanoscale domains known as “polar nanoregions” (PNRs), the chemical origin of these domains have not been studied extensively. Here, we apply precise and accurate aberration-corrected scanning transmission electron microscopy (STEM) in order to probe atom column specific, picometer scale displacements in prototypical relaxor lead magnesium niobate (PMN). Combined with the chemical sensitivity of high angle annular dark-field imaging (HAADF), we relate local chemistry to the local structure of PMN. In this talk, we provide a study of local polarization and its relation with local chemistry along multiple zone axes in PMN. We apply advanced spatial statistics in order to elucidate possible correlation between chemistry and structure in these complex materials. Combining experiment with STEM image simulation, we are able to provide direct correlations between compositional disorder and local polarization in these complex relaxor ferroelectric materials.

2:45 PM(EAM-ELEC-S13-026-2018) In situ TEM study of polarization fatigue in a BZT-BCT ceramicZ. Fan*1; X. Tan1

1. Iowa State University, USA

In situ transmission electron microscopy (TEM) is employed to study the domain morphology evolution during polarization fatigue in the 0.5Ba(Zr0.2Ti0.8)O3–0.5(Ba0.7Ca0.3)TiO3 (BZT–BCT) ceramic. During the very first application of electric field, the multiple domains in the grains at the virgin state are observed to transform into a large domain at an intermediate level of electric field, which has been suggested to be the origin of the ceramic’s outstanding piezoelectric properties. This single domain state is gradually disrupted and the domain wall mobility is progressively suppressed during the electric cycling. In the fatigue tests under unipolar cyclic fields, domain growth is directly observed to be blocked by the accu-mulated defects and, consequently the whole grain which contains large lamellar domains in the virgin state is gradually occupied by fragmented domains and defect clusters. In the bipolar fatigue tests, various fatigue phenomena in a number of grains are recorded, from which the fatigue resistance is found to correlate with the revers-ibility of the multiple ∈ single domain transformation. Additionally, a systematic investigation of field amplitude dependence of bipolar fatigue behavior is conducted. Distinguishable domain evolutions during electric cycling at two field amplitudes indicate distinct polarization fatigue behaviors.


Abstracts

3:00 PM(EAM-ELEC-S13-027-2018) In-situ Piezoelectric Response Measurements of Lead-free, Bismuth-based, Piezoelectric Thin FilmsA. Fox*1; B. Gibbons1; H. Funakubo2

1. Oregon State University, MIME, USA2. Tokyo Institute of Technology, Japan

There is a pressing need to discover and understand the behavior of environmentally benign, non-toxic, and sustainable replacements for lead-based materials in all applications. Within piezoelec-tric applications, one class of materials that shows great promise are those which are based on bismuth sodium titanate (BNT). However, in thin film embodiments, properties and related mech-anisms do not appear to correspond to their bulk counterparts. For example, in 80Bi0.5Na0.5TiO3-20Bi0.5K0.5TiO3 and 72.5(Bi0.5Na0.5) TiO3 - 22.5(Bi0.5K0.5)TiO3 - 5Bi(Mg0.5Ti0.5)O3 thin films, a non-ergodic and ergodic system in bulk embodiments, the piezoelectric response does not exhibit the same enhanced behavior, and the response is typical of a normal ferroelectric rather than a relaxor. To be success-fully integrated as thin films for microelectronic applications, the fundamental shape-change effect in these new materials needs to be understood. In-situ measurements of crystal structure of 400 nm thick films via 2D X-ray diffraction under applied field have revealed that thin film embodiments undergo an irreversible structural change under applied field and resultant strain is almost entirely due to intrinsic effects. These measurements have begun to shed light on the differences between bulk and thin film BNT-based ceramics and thin films.

3:15 PM(EAM-ELEC-S13-028-2018) Thin film stress in piezoelectrics for adjustable opticsJ. Walker*2; T. Liu3; M. Tendulkar3; D. N. Burrows4; C. DeRoo5; E. Hertz5; V. Cotroneo5; P. Reid5; E. D. Schwarts5; T. Jackson3; S. E. Trolier-McKinstry2

2. Pennsylvania State University, Materials Research Institute, USA3. Pennsylvania State University, Electrical Engineering, USA4. Pennsylvania State University, Astronomy and Astrophysics, USA5. Harvard University, Harvard Smithsonian Center for Astrophysics, USA

Piezoelectric thin films are being developed for adjustable x-ray optics, which are x-ray mirrors that can be figure-corrected post manufacture to achieve high angular resolution. This application requires sputter deposited thin film piezoelectric actuators on the convex side, and Cr/Ir reflective layers on the concave side of curved glass substrates. Balancing the stress on each side of the mirror is critical for minimizing mirror distortion and thus understanding the factors contributing to thin film stress is critical. The stress in Ti/Pt/Pb(Zr0.52Ti0.48)0.99Nb0.01O3 (PZT)/Pt multilayers and Cr/Ir layers was studied and the influence of substrate curvature was assessed. Crystallization temperature (550C or 650C) was the most influen-tial factor on stress magnitude; layer thickness was controlled the total integrated stress (~260 MPa x µm). Non-uniform film thick-ness ranged from 9% to 20% depending on the substrate curvature for films deposited with a conventional magnetron sputter source. The thickness non-uniformity was the largest contributor to stress non-uniformity.

Advanced Electronic Materials III: Piezoelectric CrystalsRoom: Orange CSession Chairs: Qiang Li, Tsinghua University; Andrew Bell, University of Leeds

4:00 PM(EAM-ELEC-S13-029-2018) Domain configuration evolution in PMN-PT single crystals near MPB under a radial poling field (Invited)Q. Li*1; Y. Zhou1; C. XU1; Q. Yan1

1. Tsinghua University, Department of Chemistry, China

Relaxor-based ferroelectric single crystals of (1-x)Pb(Mg1/3Nb2/3) O3-xPbTiO3 (PMN-xPT) with the compositions close to morpho-tropic phase boundary (MPB), are under extensive investigations for its extraordinarily high electromechanical coupling factor (k33>0.90) and piezoelectric property (d33>2000 pC/N). However, exploring the relationships between its structure and high piezoelectric response has always been an extremely difficult, but irresistible project in past two decades. Radial electric field induced periodic polarization rota-tion Pb(Mg1/3Nb2/3)O3-0.34PbTiO3 (PMN-0.34PT) single crystals has been investigated by in-situ polarized light microscope (PLM). The domain structure evolutions could be confirmed based on optical extinction rules and the permissible domain configura-tions when polled under a special-designed radial applied field. The phase transition sequences of poled [100]- and [011]-oriented PMN-0.34PT are carefully measured upon heating, respectively. The phase transition sequences suggest that the phase stability of PMN-0.34PT crystals depends on not only the magnitude, but also the orientation of applied electric field. The radial electric field can be served as a general strategy to explore the polarization rota-tion process and domain structure evolution in ferroelectric single crystals.

4:30 PM(EAM-ELEC-S13-030-2018) Low Temperature Properties of Ferroelectric and Relaxor Materials (Invited)A. J. Bell*1

1. University of Leeds, School of Chemical and Process Engineering, United Kingdom

The discovery of the large, low temperature (~100K) dielectric relax-ation in morphotropic phase boundary (MPB) compositions of Pb(Mg1/2Nb2/3)O3-PbTiO3 (PMN-PT) single crystals has prompted a revision of the origins of the large piezoelectric activity in these materials, as the polarization rotation mechanism proposed to explain giant piezoelectric effects had not previously been consid-ered to be a temperature activated process. Here we present new cryogenic data on a number of materials including Pb(Mg1/2Nb2/3)O3-based crystals and ceramics, plus classical materials (PZT, BaTIO3). The data are compared to the possible models of enhanced piezoelectricity and dielectric relaxation including polarization rota-tion and heterophase fluctuations, in order to shed new light on the phenomena in PMN-PT.

5:00 PM(EAM-ELEC-S13-031-2018) High-Temperature Solution Growth and Characterization of (1-x)PbTiO3-xBi(Zn2/3Nb1/3)O3 Piezo-/ferroelectric Single CrystalsA. Paterson*1; J. Zhao2; Z. Liu2; X. Wu2; W. Ren2; Z. Ye1

1. Simon Fraser University, Canada2. Xi’an Jiaotong University, China

Piezoelectric and ferroelectric materials form an important class of functional materials that may be used as electromechanical trans-ducers. PbTiO3-Bi(Me’Me”)O3 solid solutions have been studied because of their high Curie temperatures (TC) in order to extend


Abstracts

the operating temperature range for potential applications. To this end, novel ferroelectric single crystals of the (1-x)PbTiO3-xBi(Zn2/3Nb1/3)O3 (PT-BZN) solid solution were successfully grown by the high-temperature solution growth (HTSG) method. The dielectric permittivity and optical domain structures were charac-terized by dielectric measurements and polarized light microscopy, respectively, as a function of temperature, revealing a first-order ferroelectric-paraelectric phase transition at a TC of 436 ± 2 °C. Based on the TC, the average composition of the crystal platelet was estimated to be 0.58PT-0.42BZN. Piezoresponse force microscopy measurements of the phase and amplitude as a function of voltage reveal the complex polar domain structure and demonstrate the ferroelectric switching behaviour of these materials. These results suggest that the PT-BZN single crystals form a new family of high TC piezo-/ferroelectric materials which are potentially useful for the fabrication of electromechanical transducers for high-temperature applications.

5:15 PM(EAM-ELEC-S13-032-2018) Ferroic and Multiferroic Behavior in Fe doped BaTiO3 single crystalsM. Staruch*1; M. Cain2; P. Thompson3; P. Finkel1

1. U.S. Naval Research Laboratory, USA2. Queen Mary University of London, United Kingdom3. European Synchrotron Radiation Facility, France

Single crystals of BaTiO3 (BTO) that have been doped at the titanium site with Fe3+ or Mn3+ have previously been shown to demonstrate large and recoverable electrostrain of up to 0.8 % that is thought to be due to the alignment of defects (i.e. O2- vacancies) with the crys-tallographic symmetry in the ferroelectric state when the samples are aged.[1,2] This results in a restoring force where the ferroelec-tric domains favour alignment with the defect dipoles, giving rise to a large reversible strain due to repeated non-180o domain rotation. There is also the possibility that the incorporation of a magnetic ion could give rise to a magnetic signature and even possibly multifer-roic coupling in these doped samples, the possibility of which has not been previously investigated. In this presentation, results from magnetic measurements and polarization measurements with bias magnetic fields will be discussed for a 0.5% Fe doped BTO crystal. Impact of repeated cycling at different electric fields and the recover-ability of this large strain will also be presented.

5:30 PM(EAM-ELEC-S13-033-2018) Highly sensitive mechanical pressure detection by piezoelectric AlN thin filmsH. Bishara*1; S. Berger1

1. Technion - Israel Institute of Technology, Materials Science and Engineering, Israel

Detection of ultra-small applied mechanical pressures in the scale of few Pascals is required in various fields such as medical diagnosis, gas leak detection and robotics. The piezoelectric effect enables detection of a mechanical pressure by a change of dielectric polariza-tion of the material. High detection sensitivity to applied mechanical pressure in the scale of few Pascals is reported in this research work in thin AlN films having a unique preferred crystallographic orien-tation and negligible internal residual stress. AlN thin films are deposited on flexible polycrystalline aluminum foils where the aluminum grains have a preferred [100] crystallographic orientation in-vertical to the surface plane of the foil. The AlN films were depos-ited by using the rf reactive sputtering method of pure aluminum target in the presence of a nitrogen gas. Different preferred crys-tallographic orientation of the AlN grains relative to the film plane were formed at different deposition temperatures. A solid correla-tion between the crystallographic orientation of the AlN grains, the internal residual stress in the grains and the detection sensi-tivity of applied mechanical pressures was found. This correlation

is presented and explained based on atomic bonds mismatch at the AlN film /Al foil interface.

5:45 PM(EAM-ELEC-S13-034-2018) Combinatorial studies on the effect of boron addition to the aluminum-scandium nitride systemK. R. Talley*1; G. L. Brennecka1; S. Manna1; A. Zakutayev2; C. Packard1; C. Ciobanu1; Y. Chen1

1. Colorado School of Mines, Metallurgical Materials and Engineering, USA2. National Renewable Energy Laboratory, USA

The aluminum-scandium nitride material system has been the atten-tion of significant focus for its promise of improved performance in wireless bandpass filter devices. Limitations to the aluminum-scan-dium nitride systems adoption include the reduction in material stiffness, reduction in film orientation, and the cost of scandium metal. This study investigates the addition of boron to the alloy system as to improve each of these limitations. Boron nitride is known as a very hard material and is hypothesized to improve the mechanical properties. Boron is smaller in size than aluminum and should compensate the strain induced by the larger scandium atoms, improving the crystal quality. Boron is also cheaper to produce, which can lower the cost to produce these films in micro electromechanical systems. Thin film combinatorial synthesis and characterization was used to investigate the Al1-x-yScxByN system. Here we present the calculated structural, piezoelectric, mechanical, and electrical properties and the dependence on the composition of the material, along with initial observations from experimental synthesis.

Friday, January 19, 2018


Data Science and High-throughput Approaches IRoom: Citrus BSession Chair: Mina Yoon, Oak Ridge National Laboratory

8:30 AM(EAM-JOINT-001-2018) Informatics and the Materials Tetrahedron (Invited)R. LeSar*1

1. Iowa State University, Materials Science and Engineering, USA

Materials informatics is a field of study that applies the princi-ples of informatics to accelerate the understanding, discovery, and development of materials. Informatics is a field of research in which information science, processing, and systems combine to examine the structure and behavior of information, enabling new ways to access and explore that information. In materials, information comes in many forms, as does the possible use of that information, and the potential applications of informatics are equally diverse. In this talk we will discuss the various uses of informatics in mate-rials research and development, from first-principles combinatorial calculations that search the space of stable compounds and interface structures to the analysis and quantification of complex microstruc-tures. Emphasis will be given to the combination of experiments and computational modeling with materials data science and informatics to provide a practical path to replacing the historical paradigm of empirical materials development.


Abstracts

9:00 AM(EAM-JOINT-002-2018) Data Analytics using Canonical Correlation Analysis and Monte Carlo Simulation (Invited)J. Rickman*1

1. Lehigh University, Materials Science and Engineering, USA

We describe the use of correlation analyses, coupled with Monte Carlo simulation, to solve data-intensive problems in materials science and engineering. With this approach, one can identify important, possibly non-linear, relationships among materials processing variables and properties, thereby reducing the dimen-sionality of large data spaces. We demonstrate the utility of our approach by considering two applications, namely 1.) determining the interdependence of processing and microstructural variables associated with doped polycrystalline aluminas, and 2.) relating microstructural descriptors to the electrical and optoelectronic prop-erties of thin-film solar cells. Finally, we describe how this approach facilitates experimental planning and process control.

9:30 AM(EAM-JOINT-003-2018) Disrupting the Ceramic R&D Model and Discovery of Processing-Structure-Property Relationships through Automated Characterization and Data ScienceM. C. Golt*1

1. U.S. Army Research Laboratory, USA

For decades, the R&D of ceramics and the discovery of processing-structure-property relationships has followed a process→characterize→analyze→adjust→repeat loop. While tech-nologies have advanced over the years, characterization and analysis remain the time-limiting steps. This places a constraint on the number of material variants that can be thoroughly evaluated. The end result of this slow and tiresome process is less structure-prop-erty data to populate the Materials Genome. To help fully realize the vision of the Materials Genome Initiative, an approach is presented to disrupt the traditional discovery loop method with an auto-mated, non-destructive characterization technology that can batch characterize the microstructural features of a large population of samples manufactured with a range of compositions and processing scenarios. This enables the generation of large datasets that are rapidly analyzed through machine learning and data visualization techniques to determine the causality between the input processing and the output structure and properties. With these efficiencies, a new R&D model is proposed to accelerate discovery and completion of Materials Genome information. The application of this model is demonstrated on thousands of silicon carbide specimens, where changes in the electrical properties are observed.

10:15 AM(EAM-JOINT-004-2018) Informatics Driven Design of Ceramics (Invited)K. Rajan*1

1. University at Buffalo: the State Univ. of New York, Materials Design and Innovation, USA

In this presentation we explore how one can use informatics to not only discover new materials chemistries but also to how to discover pathways for that discovery. We show these pathways that help to bridge the gap between fundamental materials properties and struc-ture and materials performance. This presentation will focus on how data science methods can discover new pathways for the chemical design of complex multicomponent ceramics.

10:45 AM(EAM-JOINT-005-2018) Density functional theory calculations and data mining for new thermoelectrics discovery (Invited)A. Jain*1

1. Lawrence Berkeley National Laboratory, USA

In this talk, I will describe our efforts to compute the electronic transport properties of 60,000 materials from the Materials Project database (www.materialsproject.org) to discover new bulk thermo-electric materials. This computational data set is available openly to researchers in the community. I will summarize the calculation procedure and approximations employed and introduce our open-source automation framework, atomate, that can be freely used by other research groups to produce such large data sets. I will discuss new materials predicted by the high-throughput computational screening effort and their experimental synthesis and character-ization by collaborators. Finally, I will introduce matminer, our platform for data mining in materials, and its application to mate-rials design. This includes structure and band structure similarity metrics that can be used to better understand structure-property relationships as well as guide one towards interesting materials candidates for target applications.

11:15 AM(EAM-JOINT-006-2018) High-throughput powder exploration method for materials informaticsK. Fujimoto*1; A. Aimi1; S. Maruyama2

1. Tokyo University of Science, Japan2. Tohoku University, Japan

Computational chemistry or machine learning using an enormous database is used for prediction of functional materials. Especially in the field of ceramics synthesis, the experimental conditions are different for each researcher. It causes the difference of crystal struc-ture, crystallite size, physical properties etc. among literatures, even in the same composition. To improve the accuracy of prediction in materials informatics, it is necessary to construct a material library database under specific circumstances. We have constructed a combinatorial system based on a wet process and have been working on the search for multinary lithium secondary battery cathode materials and thermoelectric materials. For example, in exploring for substitute materials for layered rock salt type Li(Ni,Co,Ti)O2, replacing Ti with 10% in Co site showed better cycle performance. Fujimoto et al. have developed a high-throughput X-ray diffractom-eter for investigating the correlation between phase and physical properties. However, we thought that structural refinement data collected using synchrotron radiation would be required as one of the data descriptors in future materials informatics. So, we devel-oped a new efficient measurement tool for powder samples in synchrotron radiation facility, and also examined algorithms for refining the structure data.

11:30 AM(EAM-JOINT-007-2018) Scoping the Polymer Genome: Rational Design of Polymer Dielectrics (Invited)A. Mannodi-Kanakkithodi*1; H. D. Tran2; C. Kim2; R. Ramprasad2

1. Argonne National Lab, Center for Nanoscale Materials, USA2. University of Connecticut, USA

To date, trial and error strategies guided by intuition have dominated the identification of materials suitable for a specific application. We are entering a data-rich, modeling-driven era where such Edisonian approaches are gradually being replaced by rational strategies which couple predictions from advanced computational screening with targeted experimental synthesis and validation. Consistent with this emerging paradigm, we propose a strategy of hierarchical modeling with successive down-selection stages to accelerate the identifi-cation of polymer dielectrics that have the potential to surpass “standard” materials for a given application. Specifically, quantum


Abstracts

mechanics based combinatorial searches of chemical and configu-rational spaces, supplemented with data-driven (machine learning) methods are used. These efforts have led to the identification of several new organic polymer dielectrics within known generic polymer subclasses (e.g., polyurea, polythiourea, polyimide), and the recognition of the untapped potential inherent in entirely new and unanticipated chemical subspaces offered by organometallic polymers. The challenges that remain and the need for additional methodological developments necessary to further strengthen this rational collaborative design concept are then presented.

12:00 PM(EAM-JOINT-008-2018) Beyond High-throughput: Towards an Optimal, Autonomous Computational Materials Discovery Platform (Invited)R. Arroyave*1; A. Talapatra1; S. Boluki2; X. Qian2; E. R. Dougherty2

1. Texas A&M University, Materials Science and Engineering, USA2. Texas A&M University, Electrical and Computer Engineering, USA

To accelerate the materials discovery process, high-throughput (HT) computational and experimental methods have been proposed. Unfortunately, current HT computational and experimental approaches have severe limitations as they: (1) are incapable of dealing with the high dimensionality and complexity of the materials design space; (2) employ hardcoded workflows and lack flexibility to iteratively learn and adapt based on the knowledge acquired to assure balanced exploration and exploitation of the materials design space; (4) are suboptimal in resource allocation as experimental decisions do not account for the cost and time of experimentation. In this talk, we present some preliminary work in which we have adapted ideas from fields as diverse as Artificial Intelligence, Optimal Experimental Design, Global Optimization and Game Theory to develop a frame-work capable of optimally exploring the materials design space in order to attain an optimal materials response. Specifically, we use variants of the Efficient Global Optimization algorithm to deploy an autonomous computational materials discovery platform capable of performing optimal sequential computational experiments in order to find optimal materials. Moreover, we show how this framework can be made robust against selection of non-informative features by using so-called Bayesian Model Averaging approaches.


Chalcogenide Thin Films and HeterostructuresRoom: Citrus ASession Chairs: Jayakanth Ravichandran, Columbia University; Rafael Jaramillo, Massachusetts Institute of Technology

8:30 AM(EAM-ELEC-S1-012-2018) New Phase Transitions in Atomically Thin Quantum Materials (Invited)A. Tsen*1

1. University of Waterloo, Canada

We have recently demonstrated an experimental platform to isolate 2D quantum materials that are unstable in the ambient environ-ment. I will discuss our studies of the charge density wave (CDW) compound 1T-TaS2 and Weyl semimetal 1T’-MoTe2 in the atomi-cally thin limit, made possible using this technique. In TaS2, we 1) find that the lock-in CDW transition becomes increasingly meta-stable in thin samples, 2) demonstrate electrical control over this transition, 3) spatially image the growth of CDW domains, and 4) uncover a new surface CDW transition distinct from that in the bulk

layers. In MoTe2, lowering dimensionality suppresses the interme-diate centrosymmetric phase, driving the Weyl ground state up to and beyond room temperature. The changing electronic structure of thin samples are studied by magnetotransport at low temperature.

9:00 AM(EAM-ELEC-S1-013-2018) High-quality growth of chalcogenide topological insulators (Invited)S. Law*1

1. University of Delaware, Materials Science and Engineering, USA

Chalcogenide topological insulators (TIs), including Bi2Se3, Bi2Te3, and Bi2(Se(1-x)Tex)3, are of significant interest due to their unique band structure. These materials have a bulk bandgap crossed by surface states that exhibit linear dispersion and spin-momentum locking. The Dirac electrons in these surface states are low-mass, spin-polarized, and unable to backscatter, making them a tantalizing prospect for applications in optics, electronics, and spintronics. Unfortunately, many TI films exhibit significant bulk conductivity and unstable properties upon exposure to air, making it difficult to access the topological electrons and design real-world devices. In this talk, I will describe our recent results on the growth of chalcogenide TIs. By using a combination of chalcogenide cracking sources, annealing techniques, alloying, lattice-matched virtual substrates, and capping layers, we have been able to reduce the bulk carrier density by more than a factor of two in our films, allowing access to the topological surface electrons. Furthermore, our films are stable in air for over 60 days. I will present x-ray diffraction, atomic force microscopy, and optical data showing how the film quality depends on various growth parameters. Further refinements to our growth procedures may completely eliminate the bulk electrons, leading to long-awaited TI devices.

9:30 AM(EAM-ELEC-S1-014-2018) Single crystal growth, characterization, and in situ manipulation of van der Waals gapped CuInP2S6/In4/3P2S6 heterostructuresM. A. Susner*1; M. McGuire2; P. Ganesh2; M. Chyasnavichyus2; P. Maksymovych2

1. AFRL, Aerospace Systems Directorate, USA2. Oak Ridge National Lab, USA

The 2D metal thiophosphates (MTPs) are comprised of van der Waals gapped layers of metals intercalating lamellae of [P2S6]4- anions. In many ways MTPs are the 2D equivalent of complex oxides in that the ferroic correlations of atomic positions and magnetic moments in this materials family are sensitively dependent on structure and chemistry. After briefly introducing this materials family, I will focus on the synthesis of ferrielectric CuInP2S6/In4/3P2S6 heterostructures where both phases are located in the same single crystal. The ratio of these two phases can be manipulated so as to increase the TC from 315 K to 360 K. Interestingly, the morphology of the two phases can be manipulated by adjusting the cooling rate from above 500 K due to the presence of a cation eutectic point. As a result, varying the cooling rate through the phase transition controls the lateral extent of chemical domains over several decades in size. At the fastest cooling rate, the dimensional confinement of the ferrielectric CuInP2S6 phase to nanoscale dimensions suppresses ferrielectric ordering due to the intrinsic ferroelectric size effect. Intralayer heterostructures can be formed, destroyed, and re-formed by thermal cycling, thus enabling the possibility of finely tuned ferroic structures that can potentially be optimized for specific device architectures.


Abstracts

9:45 AM(EAM-ELEC-S1-015-2018) Persistent photoconductivity due to hole-hole correlation in chalcogenides, with applications to neuromorphic computing and chemical sensorsR. Jaramillo*1

1. Massachusetts Institute of Technology, USA

Large and persistent photoconductivity (PPC) in semiconductors is due to the trapping of photo-generated minority carriers at crystal defects. Theory has suggested that anion vacancies in II-VI semi-conductors are responsible for PPC due to negative-U behavior, whereby two minority carriers become kinetically trapped by lattice relaxation following photo-excitation. By performing a detailed analysis of PPC decay at long times in CdS, we provide experimental support for this negative-U model of PPC. We also show that PPC is correlated with sulfur deficiency. We use this understanding to vary the photoconductivity of CdS films over nine orders of magnitude by controlling the activities of Cd2+ and S2- ions during chemical bath deposition. We suggest a screening method to identify materials with long-lived, photo-excited states based on the results of ground-state calculations of atomic rearrangements following defect redox reactions. Understanding and controlling PPC in II-VI materials informs their application in thin film solar cells, and may enable new applications such as electro-optic elements in neuromorphic imaging systems and in chemical sensors. We will discuss the role of PPC in enabling artificial synaptic behavior and as a transduction mechanism in chemical sensors.

10:30 AM(EAM-ELEC-S1-016-2018) Laser-Assisted Synthesis, Processing, and Spectroscopy of 2D Metal Chalcogenides and Heterostructures (Invited)M. Mahjouri-Samani*1

1. Auburn University, Electrical and Computer Engineering, USA

Recently, two-dimensional (2D) materials have emerged as an exciting new class of materials with unique properties and poten-tial application in next-generation electronics, photonics, as well as energy and biological devices. In this talk, I will present the approaches I have undertaken to understand and control the forma-tion of 2D materials and heterostructures with tailored properties, through the development of laser-assisted synthesis, processing, and diagnostic approaches. These approaches are designed to form and deliver atoms, clusters, or nanoparticles with tunable kinetic energies to promote the growth of 2D metal chalcogenides with controlled stoichiometry, orientation, number of layers, crystallite size, and growth location. I will also show how the atomic component with tunable kinetic energy is essential for healing defects, doping, alloying, and conversion of 2D monolayers. Laser characterization methods, such as Raman and photoluminescence spectroscopy are used to reveal different aspects relating synthesis and function such as atomistic stacking configurations between layers, band gap shifts due to doping, and the nature of defects. The combination of these laser-based synthesis, processing, and spectroscopy approaches provide unique opportunities for the development of, combinatorial, and rapid screening methods for accelerated discovery of materials.

11:00 AM(EAM-ELEC-S1-017-2018) Electronic and optical properties of 2D-In2Se3

A. Janotti*1; W. Li1; F. Sabino1


Indium selenide, with formula unit In2Se3, has been found in a variety of phases, including van der Waals bonded 2D structures. The two-dimensional β-phase of In2Se3 share the same crystal structure as the topological insulator Bi2Se3, and has been used in (In,Bi)2Se3 alloys for band gap engineering. In2Se3 is a semiconductor material that is promising for a series of high technological applications such

as for phase-change memory, thermoelectrics, and photodetectors. It has been reported that few layers of In2Se3 have strong photocon-ductive response into ultraviolet, visible, and near-infrared spectral regions. However, basic properties of the different phases of In2Se3 have yet to be resolved, such as the precise value of the band gap and the band alignment with other semiconductor materials. Using density functional theory with the Heyd-Scuseria-Ernzerhof hybrid functional (HSE), we investigate the electronic structure and optical properties of the various phases of In2Se3, paying special attention to the differences between the fundamental and optical band gaps. We also discuss the position of the band edges with respect to other semiconductors, and compare our results to available experimental data and previous calculations.

11:15 AM(EAM-ELEC-S1-018-2018) Imaging orbitals and defects in superconducting FeSe/SrTiO3

C. E. Matt*1; T. Webb1; H. Pirie1; D. Huang1; S. Fang1; E. Kaxiras1; J. Hoffman1

1. Harvard University, Dept. of Physics, USA

Single-layer FeSe grown epitaxially on SrTiO3 has been shown to superconduct with Tc as high as 100 K, an order of magnitude higher than bulk FeSe. This dramatic enhancement motivates intense efforts to understand the superconducting pairing mechanism. Nematicity – the breaking of 4-fold symmetry – has been proposed as an important factor. Atomic defects may be used to probe or manipulate the electronic structure – by scattering electrons, pinning nematic fluctuations, or locally suppressing superconduc-tivity. Here we use scanning tunneling microscopy (STM) to search for orbital nematicity in single-layer FeSe/SrTiO3, and to investigate atomic-scale defects that locally influence superconductivity. From quasiparticle interference (QPI) images, we disentangle scattering intensities from the orthogonal Fe 3dyz and 3dyz bands and place an upper bound of δr ∼ 20 nm on nematic domain size. Furthermore, we identify “dumbbell”-shaped atomic-scale defects as Fe vacancies, which occur under certain growth conditions.

11:30 AM(EAM-ELEC-S1-020-2018) Cross-interface coupling of electrons and phonons in oxide-chalcogenide heterostructuresR. Moore*1

1. SLAC National Accelerator Laboratory, USA

The recent synthesis of interfaces and heterostructures with atomic precision has revealed numerous new and unexpected phenomena. The order of magnitude enhancement of the superconducting properties of FeSe in the ultrathin 2D limit is an example of such a surprise. In this talk I will discuss recent efforts to combine molec-ular beam epitaxy (MBE) with various in situ and ex situ techniques to determine the origins of the Tc enhancement. Angle resolved photoemission spectroscopy (ARPES), reveals how the electrons in the FeSe monolayer couple with the phonons in the underlying oxide substrate to boost the superconducting properties to record breaking Tc’s for this class of materials. Time resolved ARPES (tr-ARPES) and time resolved x-ray diffraction (tr-XRD) are combined in a lock-in experiment to quantify the electron-phonon coupling in these materials with femtosecond precision. Theory suggests there is nothing special about FeSe and efforts to control the cross-interface coupling in oxide heterostructures will be discussed.


Abstracts


Imaging and Analytical Techniques IIRoom: Magnolia A/BSession Chairs: David McComb, The Ohio State University; Julian Walker, Pennsylvania State University; Abhijit Pramanick, City University of Hong Kong; Hugh Simons, Technical University of Denmark

8:30 AM(EAM-ELEC-S3-015-2018) Relaxor-ferroelectric domain structure in Pb(Mg1/3Nb2/3)O3 and Pb(Sc1/2Nb1/2)O3-based polycrystalline materials determined by piezo-response force microscopy (Invited)H. Uršič*1; M. Otonicar1; T. Rojac1; M. Vrabelj1; B. Malic1

1. Jozef Stefan Institute, Electronic Ceramics Department, Slovenia

Functional properties of relaxor-ferroelectric polycrystalline mate-rials mainly depend on their composition and are influenced by its crystal and domain structures. The domain structure and the mobility of domain walls can be efficiently determined using piezo-response force microscopy (PFM). In relaxor-ferroelec-tric (1-x)Pb(Mg1/3Nb2/3)O3–xPbTiO3 (PMN–PT) by increasing the PT content, the crystal symmetry changes from pseudocubic in PMN towards rhombohedral, monoclinic and, finally, tetrag-onal symmetry. Following the changes in symmetry, by PFM we have observed that domains evolve from nano-sized domains in composition with small amount of PT towards 100nm-sized ‘square-shaped’ rhombohedral domains, further into irregular monoclinic domains, and finally to micrometer-sized lamellar domains on the tetragonal side of the PMN–PT compositions. On the other hand, in Pb(Sc1/2Nb1/2)O3, the evolution from micrometer-sized to nano-sized domains appears by increasing the temperature up to the ferro-electric-relaxor crossover. Further, the domain structure of these compositions in the poled state, i.e. the state in which the piezo-electrics are used in transducers, actuators and sensors, will also be discussed.

9:00 AM(EAM-ELEC-S3-016-2018) Nanoscale three-dimensional imaging of ferroelectric and electronic properties in multiferroic BiFeO3 thin filmsJ. Steffes*1; B. Huey1; R. Ramesh2

1. University of Connecticut, Materials Science and Engineering, USA2. University of California, Berkeley, Materials Science and Engineering,

USA

Cross-sectional imaging of ferroelectric thin films using an atomic force microscope (AFM) is presented. In addition to imaging the two-dimensional surface of a thin film, high-resolution piezore-sponse force microscopy (PFM) and contuctive AFM (CAFM) data sampled throughout the thickness of a thin film allows for a full three-dimensional reconstruction of functional ferroelectric and multiferroic properties in BiFeO3 epitaxial thin films. Using such techniques, various structure-property relationships in ferroelectric materials can be assessed as a function of thickness between one and several hundred nanometers, including the ferroelectric coercive field, polarization reversal dynamics, and conductivity of multifer-roic domain walls. Sub-nanometer resolution in the “z” dimension provides unprecedented precision for data acquired via AFM, and also the ability to measure phenomena otherwise obscured or

invisible in thicker films. In addition, cross-sectional AFM allows for imaging and analysis of buried layers not otherwise visible by conventional AFM, which provides both complementary data to transmission electron microscopy (TEM) cross-sectional images, as well as new insights into the relationship between strain and ferro-electricity in epitaxial heterostructures.

9:15 AM(EAM-ELEC-S3-017-2018) Probing strain in oxide heterostructures and ultrathin films by Raman spectroscopy (Invited)J. Kreisel*1

1. Luxembourg Institute of Science and Technology, Materials Research and technology, Luxembourg

Over the past two decades, a significant progress has been achieved in the epitaxial growth of (multi-) functional oxide films. By applying epitaxial strain to thin films, ferroic transition temperatures can be increased by hundreds of degrees, new phases can be induced or the coupling between different ferroic orders can be modified. Due to the low film thickness and the often-subtle structural modifi-cations, the structural characterization of functional oxide thin films, especially in heterostructures and in the ultra-thin regime, remains challenging. Here, we present evidence that tensile and compressive strain can induce multiple phase transitions in LaNiO3 films and heterostructures and that the different phases and subtle modifi-cations can be traced by Raman scattering even in ultra thin layers down to 1.2 nm of thickness.

9:45 AM(EAM-ELEC-S3-018-2018) In-situ imaging of long-range symmetry breaking in ferroelectric ceramicsH. W. Simons*3; A. B. Haugen2; C. Detlefs5; H. F. Poulsen3; J. Daniels4; D. Damjanovic1

1. Swiss Federal Institute of Technology in Lausanne - EPFL, Ceramics Laboratory, Switzerland

2. Technical University of Denmark, Energy conversion and storage, Denmark

3. Technical University of Denmark, Physics, Denmark4. University of New South Wales, Materials Science & Engineering,

Australia5. ESRF, France

The characteristic functionality of ferroelectric materials is due to the symmetry of their crystalline structure. Piezoelectricity - their most widely used functional property - is a direct consequence of the coupling between spontaneous polarization and spontaneous strain arising at the symmetry-breaking phase transition into the ferroelectric state. Ferroelectrics therefore lend themselves to design approaches that exploit the definitive role of structural symmetry by introducing extrinsic strain. Using in-situ dark-field x-ray micros-copy to map lattice distortions around deeply embedded domain walls and grain boundaries in BaTiO3, we reveal that symme-try-breaking strain fields extend up to several micrometers from domain walls - orders of magnitude more than presently assumed. As this exceeds the average domain width, no part of the material is elastically relaxed, and symmetry is universally broken. Such extrinsic strains are pivotal in defining the local properties and self-organization of embedded domain walls, and must be accounted for by emerging computational approaches to material design.


Abstracts

Multiscale Structure Property Relationships IIRoom: Magnolia A/BSession Chairs: Abhijit Pramanick, City University of Hong Kong; Julian Walker, Pennsylvania State University

10:30 AM(EAM-ELEC-S3-019-2018) Synergetic Effects between Experimental Studies and Simulation to Reveal Mechanisms Involved in Resistance Degradation (Invited)T. J. Bayer*1; J. Wang1; J. Carter1; R. Wang1; S. Sahu1; A. Klein2; L. Chen1; C. Randall1

1. Pennsylvania State University, Materials Science and Engineering, USA2. TU Darmstadt, Institute of Materials Science, Germany

Computational efforts including the simulation of charge transport in non-linear dielectrics are an important contribution to improve the understanding and predictability of device behavior such as resistance degradation. However, the quality of a model strongly depends on the provided experimental data. For charge transport simulations it is crucial to use spatio-temporal changes in conduc-tivity as reference instead of temporal changes of the effective conductivity. This is obtained by in-situ impedance studies which allowed to develop a more predictive hierarchical multiscale simu-lation approach that includes oxygen vacancy migration, charge injection, and the relevant defect chemistry of the dielectric. Here, simulations guided the understanding of the impedance data, while in return, impedance data improved the model. First, the focus will be on this synergetic effect between experiment and simulation. In addition, the need for further experimental methodologies will be emphasized to further improve the model and develop design strategies for robust and long-lifetime dielectric materials. Among various techniques, measurements of the thermally stimulated depo-larization current are highlighted that reveal essential insights on the impact of defect complex dissociation and association during degra-dation and recovery.

11:00 AM(EAM-ELEC-S3-020-2018) Actuation Mechanisms in Core-Shell Structured BiFeO3-BaTiO3 Ceramics (Invited)D. A. Hall*1

1. University of Manchester, School of Materials, United Kingdom

Bismuth ferrite-barium titanate (BF-BT) ceramics have generated much interest due to their intriguing dielectric, piezoelectric and multiferroic properties. The present research is concerned with 0.75BF-0.25BT solid solutions that are donor-doped with 1% of Ti4+ ions on the Fe3+ sites in order to suppress electronic conductivity. It is shown that the as-sintered ceramics exhibit a core-shell type microstructure comprising a BF-rich rhombohedral ferroelectric core with a BT-rich pseudo-cubic relaxor ferroelectric shell. Such materials show a largely reversible ferroelectric switching behaviour, with constricted polarisation-electric field hysteresis loops. The application of a thermal quenching procedure induces a transforma-tion to a long-range ordered ferroelectric phase in the shell region and thereby enhances the ferroelectric properties. The electrome-chanical actuation mechanisms in BF-BT ceramics were evaluated using in-situ high energy XRD, with supporting data from dielec-tric permittivity, PFM and macroscopic strain measurements. The results of these studies demonstrate that the electric field-induced strain at room temperature is dominated by ferroelectric switching and lattice strain in the shell region, with the core providing an addi-tional contribution at elevated temperatures.

11:30 AM(EAM-ELEC-S3-021-2018) Polarization and strain dynamics in polycrystalline ferroelectric/ferroelastic materials: An experimental approach and mechanistic descriptionJ. Schultheiß1; Y. A. Genenko1; R. Khachaturyan1; L. Liu2; J. Daniels2; J. Koruza*1

1. TU Darmstadt, Germany2. University of New South Wales, Australia

Ferroelectric/ferroelastic polycrystalline materials are used in various electronic applications under dynamic or changing electric fields. Therefore, a detailed understanding of their switching dynamics is required. The existing models consider only polarization dynamics and assume that switching takes place by one event occurring at a characteristic switching time or over a distribution thereof, while experimental evidence indicates the presence of multiple steps. Here, we present an experimental approach for simultaneous measure-ment of polarization and strain over a broad time domain during the application of high voltage pulses that switch the polarization direc-tion. The switching dynamics of various Pb(Zr,Ti)O3 compositions were evaluated. The macroscopic response was complemented with in situ synchrotron diffraction experiments. This enabled the deter-mination of the non-180° domain wall dynamics and lattice strains. Results revealed a sequence of several switching steps, including one 180° and two non-180° switching events. A model is suggested, which allows to extract the characteristic switching times and acti-vation fields. The experimental determination of the switching sequence and associated time constants is an important requirement for future theoretical considerations of ferroelectrics.

11:45 AM(EAM-ELEC-S3-022-2018) Stabilization of Polar Nano Regions in Pb-free ferroelectricsA. Pramanick*1; W. Dmowski2; T. Egami2; A. Budisuharto1; F. Weyland3; N. Novak3; A. Christianson2; D. Abernathy2; M. Jorgensen4

1. City University of Hong Kong, Hong Kong2. Oak Ridge National Lab, USA3. Technical University Darmstadt, Germany4. Aarhus University, Denmark

Formation of polar nano regions (PNRs) through solid-solution additions are known to enhance significantly the functional prop-erties of ferroelectric materials. Despite considerable progress in characterizing the microscopic behavior of PNRs, understanding their real-space atomic structure and dynamics of formation remains a considerable challenge. Here, using the method of dynamic pair distribution function (DPDF), we provide direct insights into the role of solid-solution additions towards the stabilization of PNRs in the Pb-free ferroelectric of Ba(Zr,Ti)O3. It is shown that for an optimum level of substitution of Ti by larger Zr ions, the dynamics of atomic displacements for ferroelectric polarization are slowed sufficiently, which leads to increased local correlation among dipoles below THz frequencies. The DPDF technique demonstrates unique capability to obtain insights into locally correlated atomic dynamics in disordered materials, including new Pb-free ferroelectrics, which is necessary to understand and control their functional properties.

12:00 PM(EAM-ELEC-S3-023-2018) Electric field-induced transitions in electro-active materials (Invited)G. Viola*2; J. Walker1; Y. Tian5; M. Salvo2; M. Reece3; H. Yan3

1. Pennsylvania State University, Materials Research Institute, USA2. Politecnico di Torino, Italy3. Queen Mary University of London, United Kingdom5. Jiatong University, China

Electric field-induced transitions represent an intriguing phenom-enon which manifests itself as a modification of the crystal structure and domain configuration, observed in a wide range of electro-active


Abstracts

materials, when they are subjected to the application of an external electric field. Key examples of materials undergoing these types of transformations are represented by antiferroelectrics, ferrielectrics and relaxors, which experience transitions from a non-polar, anti-polar or weakly-polar to a polar phase during electrical loading. The degree of reversibility of these transitions depends on a number of factors, including composition, grain size and temperature, which in turn affect the polarization and strain associated with the trans-formations. The understanding of the mechanisms underlying these transitions ishighly relevant for the development of actuators and energy storage capacitors. In this talk, the most interesting features of electric field-induced transitions will be reviewed by highlighting generalities and peculiarities observed in different systems, including BaTiO3-, Bi0.5Na0.5TiO3-, BiFeO3- and AgNbO3-based ceramics. Additionally, a brief overview of novel antiferroelectric intermetallic compounds, possibly experiencing electric field-induced transition, will be given, with the purpose of stimulating interest for the study and development of alternative electro-active materials.


Novel Ion Conducting MaterialsRoom: Cypress A/BSession Chairs: Fanglin (Frank) Chen, University of South Carolina; Ho Nyung Lee, Oak Ridge National Lab

8:30 AM(EAM-ELEC-S5-011-2018) 3D Printing of Protonic ceramic Energy devices (Invited)S. MU2; Y. Hong1; J. Lei1; Z. Zhao1; F. Peng1; H. Xiao1; J. Tong*1

1. Clemson University, USA2. Clemson University, USA

Protonic ceramics have high proton conductivities at low tempera-tures for promising ceramic fuel cells and electrolysis cells, catalytic membrane reactors, H2 or steam permeation membranes, and elec-trochemical sensors. The fabrication technologies to cost-effectively obtain protonic ceramic energy devices (PCEDs) with high efficiency and reliability have attracted increasing interest recently. In previous work, we developed a solid state reactive sintering (SSRS) technique for the cost-effective fabrication of PCEDs. The PCFC button cells demonstrated very auspicious performance at 350-500oC, which provoked great interest in PCEDs. However, the manufacture of tubes, stacks, and other complicated configurations of PCEDs with large effective areas are still facing significant challenges. On the other hand, the 3D printing (3DP) technology, digital joining mate-rials layer by layer based on CAD, allows for producing complicated configurations. However, the ceramic energy devices composed of heterogeneous multilayers (e.g., dense electrolyte and porous elec-trode) demand the different consolidation conditions for the various precursors. Therefore, there is still no very successful demonstration for 3D printing of ceramic energy devices yet, especially for PCEDs. Recently, we have combined the SSRS and 3DP technologies for the fabrication of PCEDs at Clemson University. Here, we will introduce our recent work on the 3D printing of PCEDs.

9:00 AM(EAM-ELEC-S5-012-2018) Ion intercalation induced structrual change and phase transitions in epitaxial oxide thin film (Invited)Y. Du*1

1. Pacific Northwest National Lab, USA

Ion intercalation into, or removal from, structurally ordered compounds often lead to a reversible, topotactic phase transition through the displacement and/or exchange of atoms. Such funda-mental mass transport processes have been extensively investigated

for energy conversion and storage applications, particularly for use as solid-state electrolytes, mixed electronic/ionic conductors, elec-trocatalysts, and electrodes in batteries and fuel cells. In this talk, I will show that thin-film deposition by molecular beam epitaxy (MBE) allows ultrahigh purity materials of this kind to be synthe-sized, together with accurate control over their thickness, doping level, and strain state for predictable structural and property modi-fications. By combining advanced characterization, in particular in situ and environmental transmission electron microscopy, with theoretical modeling, we were able to characterize and simulate ion transport and phase transition processes at a comparable length scale to provide fundamental insight into these processes. The exam-ples we examined include oxygen intercalation into rhombohedral structured SrCrO2.8 and Brownmillerite structured SrFeO2.5, and Li intercalation into WO3 and LixCoO2 model electrodes.

9:30 AM(EAM-ELEC-S5-013-2018) Assessment of Sr2Fe1.5MoO6 as Potential Cr-tolerant Solid Oxide Fuel Cell ElectrodeL. Lei*1; F. Chen1

1. University of South Carolina, USA

Sr2Fe1.5MoO6 (SFM) has been demonstrated to possess a unique combination of redox stability, mixed ionic and electronic conduc-tivity, good chemical stability in CO2 and in H2O, and excellent catalytic activity for oxygen reduction, especially at elevated temperatures such as 800-900oC. In this study, the chemical stability, surface properties and electrochemical performance of SFM with and without Cr-contamination are evaluated to assess the feasibility of SFM as potential Cr-tolerant electrodes for solid oxide fuel cells.

9:45 AM(EAM-ELEC-S5-014-2018) A New Hybrid SOFC Catalyst for Enhanced Stability and PerformanceR. Murphy*1; Y. Chen1; S. Yoo1; K. Pei1; B. Doyle1; M. Liu1


Solid oxide fuel cells are poised to be the cleanest and most effi-cient option for generation of electricity from a wide variety of fuels, including methane and natural gas, a natural resource which is both abundant and already has a robust infrastructure. However, their high operating temperature requires high temperature stainless steel alloys to be used as electrical interconnects, which often contain chromium. Unfortunately, the current state of the art cathode mate-rial La0.6Sr0.4Co0.2Fe0.8O3-x (LSCF) degrades rapidly in the presence of chromium. We have systematically characterized the degradation behavior of the LSCF cathode under typical operating conditions and developed a new, hybrid catalyst, PrOx-PrNi0.5Mn0.5O3, to improve performance and stability. Electrochemical impedance spectroscopy, polarization measurement, and Raman spectroscopy, have been used to quantify the tolerance of the new catalyst against chromium poisoning in both symmetrical and single cells. Uniform coatings (with exsolved nanoparticles) of the catalyst have been applied to the surface of the state-of-the-art cathode using a simple solution infiltration process. The catalyst-coated cathode shows not only enhanced performance but also improved durability due to inherent chemical stability.


Abstracts

Oxygen ConductorsRoom: Cypress A/BSession Chairs: Yingge Du, PNNL; Jianhua Tong, Clemson University

10:30 AM(EAM-ELEC-S5-015-2018) High ionic conductivity at (111) fluorite-bixbyite interfaces (Invited)H. Lee*1


Achieving high ionic conductivity at low temperatures is a key requirement to develop advanced energy conversion and storage devices. Here, we develop a completely new oxide nanobrush architecture with highly enhanced ionic conductivity designed to promote flow of ions perpendicular to the substrate surface. The synthesis technique is capable of growing micron-thick single crystalline fluorite–bixbyite (CeO2–Y2O3) nanosuperlattices, in which the (111) interface is engineered to create an interfacial layer with a high density of oxygen vacancies. The resulting ionic conduc-tivity is 1000 times that achieved in bulk CeO2 with a 30% reduction in the activation energy. The spontaneous formation of the interfa-cial oxygen vacancies in the CeO2–Y2O3 nanosuperlattice is enabled by the artificial charge modulation between Y3+ and Ce4+ ions gener-ated to cope with the chemical valence mismatch. Our discovery of this fluorite–bixbyite heterostructure provides a new paradigm to develop high-performance ionic nanomaterials, to advance energy and environmental technologies, and to realize oxide nanoionics. *This work was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division.

11:00 AM(EAM-ELEC-S5-016-2018) Influence of Gallium-Based Additives on Microstructure and Ionic Conductivity of Doped-Lanthanum GallateS. L. Reis2; E. N. Muccillo*1

1. Energy and Nuclear Research Institute, Brazil2. Institute of Nuclear Energy Research, CCTM, Brazil

Sr- and Mg-doped lanthanum gallate is a well known oxide-ion conductor with potential application in Solid Oxide Fuel Cells oper-ating at intermediate temperatures (500-700oC). One of the main concerns on this solid electrolyte is related to impurity phases, frequently observed even in chemically synthesized powders, due to gallium loss during sintering. La0.9Sr0.1Ga0.8Mg0.2O3-d, LSGM, containing small amounts of Ga2O3 and Sr3Ga2O6 were prepared by solid state reaction, and the effects of the additives on micro-structure and ionic conductivity were investigated after sintering at 1350oC. Gallium oxide addition promoted grain growth of LSGM and increased the fraction of the gallium-rich impurity phase. In contrast, strontium gallate addition favored reduction of the fraction of impurity phases. The intragrain conductivity of LSGM increases with gallium oxide addition, whereas strontium gallate improved both the intra- and the intergrain conductivities of LSGM.

11:15 AM(EAM-ELEC-S5-017-2018) On the ionic conduction mechanism in B-Site acceptor doped Na0.5Bi0.5TiO3

S. Steiner1; L. Koch1; K. Meyer1; S. In-Tae1; K. Albe1; T. Frömling*1

1. Technische Universität Darmstadt, Materials Science, Germany

The ferroelectric ceramic Na0.5Bi0.5TiO3 (NBT) has been shown to obtain unexpected high oxygen ionic conductivity with Mg B-site and Sr A-site acceptor doping. Initially, a behavior like other regular ferroelectrics was assumed with hardened ferroelectric properties. Therefore, it was quite surprising that Ming Li et al. determined ionic conductivity in the range of good oxygen conductors like yttria stabilized zirconia (YSZ). Hence, new interest in this material

arose in the community investigating oxygen conducting ceramics. Until now there has been no conclusive explanation given for the extraordinarily high and rather complex temperature dependent conductivity. In this work, a possible conduction mechanism is discussed based on results of temperature and Mg concentration dependent impedance data and model calculations including data from a quantum mechanical approach. In the calculations, the defect association and phase dependent changes are taken into account elucidating the mechanism behind the experimentally obtained data.

11:30 AM(EAM-ELEC-S5-018-2018) p-type electronic conductivity in yttria-stabilised zirconia ceramic electrolytesA. R. West*1


Oxide ion conducting, yttria-stabilised zirconia, YSZ, shows increasing p-type conductivity on application of a small bias at high temperatures, which decreases on removing the bias. This is attributed to redox activity of underbonded oxide ions. Under these conditions, YSZ becomes a mixed conductor in which holes are located on oxygen. In YSZ solid solutions that have high Y content, similar levels of p-type conduction can be introduced simply by increasing the oxygen partial pressure in the surrounding atmo-sphere. The mechanism by which YSZ becomes a mixed conductor, and the possible consequences for its applications as an electrolyte in solid oxide fuel cells, will be discussed.

11:45 AM(EAM-ELEC-S5-019-2018) Conductivity Study of B-site Ga3+ Doped Na0.54Bi0.46TiO3- δ

R. Bhattacharyya*1; S. Omar1

1. Indian Institute of Technology Kanpur, Materials Science and Engineering, India

Sodium bismuth titanate (NBT) has recently drawn immense research interest because of its high oxide-ion conductivity which is comparable with Gd0.10Ce0.90O2-δ. It undergoes phase transitions from cubic to tetragonal and tetragonal to rhombohedral on cooling below 540-500°C and 400-255°C, respectively. Non-stoichiometric NBT compositions with Na/Bi>1 exhibit atleast three orders of magnitude higher conductivity than that of compositions having Na/Bi<1. Recent computational work has predicted that A-site substitution in NBT can render better conductivity than B-site doping. Based on the phase stability study, replacing Na for A-site Bi has been proposed to show high conductivity. Further, considering the factors such as the ionic size, polarizability, and bond strength with oxygen, Ga3+ appears to be a suitable dopant in the B-site of NBT for the conductivity enhancement. In the present work, we investigated the influence of Ga3+ doping in Na-excess NBT on the phase stability and conductivity. Polycrystalline dense samples of Na0.54Bi0.46Ti1-xGaxO3- δ (x = 0, 1) were prepared via solid-state reac-tion method. XRD revealed a single perovskite rhombohedral phase at room temperature. Impedance studies showed 1.5 times increase in total conductivity on 1 mol.% Ga3+ doping at 600oC. The conduc-tivity results and the ageing behavior of Na0.54Bi0.46T0.99Ga0.01O3- δ at 600oC in air and reducing conditions will be presented.


Abstracts

12:00 PM(EAM-ELEC-S5-020-2018) Optimisation of oxide-ion conductivity in acceptor-doped Na0.5Bi0.5TiO3 perovskite: approaching the limit?F. Yang2; M. Li4; L. Li2; Y. Wu2; E. Pradal Velazquez2; D. C. Sinclair*1


2. University of Sheffield, United Kingdom4. University of Nottingham, United Kingdom

Na0.5Bi0.5TiO3 (NBT) perovskite is often considered as a poten-tial lead-free piezoelectric material but it can also be an excellent oxide-ion conductor. Here we report the non-stoichiometry and oxide-ion conductivity of undoped and acceptor-doped NBT. A range of acceptor-type ions with varying doping levels are selected to incorporate into NBT or Bi-deficient NBT (nominal Na0.5Bi0.49TiO2.985; NB0.49T). Low levels of acceptors (typically < 2 at.%) can be doped on both cation sites of NBT by an ionic compensation mechanism to create oxygen vacancies and are therefore effective in enhancing the bulk oxide-ion conductivity to values of ~ 2 mS cm-1 at 400 °C. A maximum enhancement of less than 1 order of magnitude is achieved using either A-site Sr (or Ca) or B-site Mg doping in NB0.49T. This conductivity maximum is in good agreement with an oxygen-vacancy diffusivity limit model in a perovskite lattice proposed by R. A. De Souza and suggests that opti-misation of the ionic conductivity in NBT has been achieved


TransportRoom: Orange DSession Chair: Zhongchang Wang, World Permier InternationalI Research Center, Advanced Institute for Materials Research

8:30 AM(EAM-ELEC-S8-021-2018) Dielectric performance of polymer-based composites containing core-shell Ni-TiO2 particle fillersG. Jian*1; C. Zhang1; H. Shao1; C. Wong2

1. Jiangsu University of Science and Technology, Materials Science and Engineering, China


This research reports composites prepared by embedding core-shell Ni-TiO2 fillers into polydimethylsiloxane (PDMS). Micron scale Ni particles were homogeneously coated with TiO2 to give a shell thick-ness of approximately 50–200 nm. The preparation of core-shell particle is assisted by poly (vinyl pyrrolidone) (PVP) which acts as a stabilizer, a binder as well a modification polymer for changing surface energy of Ag particles. Two phases of TiO2 anatase and rutile can be obtained by heat treated at 450 °C and 800 °C. The relative permittivity of the composite containing 50 vol. % filler with rutile shell phase was approximately 550 at 100 Hz, which was more than 200 times higher than that of pure PDMS (dielectric constant equals to 2.75). The dielectric loss and breakdown voltage is measured to be approximately 0.01 at 100 Hz and approximately 100 kV/cm, which is attributed to the barrier effect of the insulating TiO2 layer. An Equivalent permittivity for core-shell particles model is used to account for the dielectric constant of the composite.

8:45 AM(EAM-ELEC-S8-022-2018) Novel Radical-based Molecular Beam Epitaxy Approach for Metal Oxide Films Containing Elements of Low Oxidation Potential (Invited)B. Jalan*1

1. University of Minnesota, USA

Metals possessing high oxidation potential are readily oxidized, whereas those with lower potential require stronger reaction condi-tions. For ternary oxides such as perovskite oxides (ABO3, where A and B are elemental metals), a difference in oxidation potentials of metal A and B can make synthesis more demanding as compared to their binary oxide counterparts. For instance, if metal B has a lower oxidation potential than that of metal A, a more severe oxidation condition may be required to achieve full oxidation of B in the pres-ence of A. We will present our recent development of the radical MBE approach, which utilizes the highly reactive metal radicals to not only overcome the oxidation challenges in oxide MBE but to also provides potential routes to grow metal oxides of elements possessing low oxidation potentials (such as V, Sn, Ni, Ir, W, etc) or in other words, elements, which are hard to oxidize under standard MBE growth conditions. Using a model materials system, a detailed study of MBE growth of BaSnO3 and SrSnO3 doping and electronic transport properties and their relationships with structural defects/disorder will be presented.

9:15 AM(EAM-ELEC-S8-023-2018) Revealing electron correlations effects in the ultraclean perovskite metal SrVO3

M. Brahlek*2; L. Zhang2; T. Birol3; R. Engel-Herbert2

2. Pennsylvania State University, Materials Science and Engineering, USA3. University of Minnesota, Department of Chemical Engineering and

Materials Science, USA

Manipulating electron-electron correlation offers a new route to engineer functional electronic materials. For the correlated ABO3 perovskites, however, non-stoichiometric defects introduced during synthesis present a challenge to understand and separate intrinsic correlation effects from the effects of extrinsic disorder. The excel-lent stoichiometric control enabled by the recently developed hybrid metal-organic-oxide molecular beam epitaxy (hMBE) technique enables the growth of ultraclean materials with intrinsic proper-ties. Here, we present detailed magnetic field-dependent Hall effect measurements of hMBE-grown SrVO3. The high mobility gives access to the high-field regime, which is a simple measurement of the carrier concentration. In contrast to the chemical expectation of 1 electron per unit cell, we find that SrVO3 is approximately 50% deficient, which is a direct measure of the modification of the ground state due to correlation effects. Further, we resolve an unex-pected hole-like carrier, whose tiny magnitude is inconsistent with the Fermi surface geometry. hMBE is thus a key technique to more broadly understand and push forward the next generation of elec-tronic materials. This work was supported by the Dept. of Energy (DE-SC0012375).


Abstracts

9:30 AM(EAM-ELEC-S8-024-2018) Reversible redox reaction of SrFe0.8Co0.2O3-δ thin films in ambient gas conditionJ. Lee1; E. Ahn2; T. Jeon3; J. Cho4; H. Jeen*1

1. Pusan National University, Department of Physics, Republic of Korea2. Pusan National University, Extreme Physics Institute, Republic of Korea3. Pohang University of Science and Technology(POSTECH), Pohang

Accelerator Laboratory, Republic of Korea4. Pusan National University, Department of Physics Education,

Republic of Korea

Low temperature reversible redox reaction in complex oxides is fascinating phenomenon, since the reaction can tune physical prop-erties as well as is a part of working principle in current renewable energy devices. For enhancing such phenomenon, topotactic oxides have been studied. Even though such reaction can take place at low temperature, it requires extreme conditions, i.e. use of oxidants and reducing agents. In this presentation, we present low temperature reversible redox reaction in ambient gas condition from epitaxial SrFe0.8Co0.2O3-δ (SFCO) thin films. Oxygen-deficient perovskite SFCO thin films have been grown on (LaAlO3)0.3-(SrAl0.5Ta0.5O3)0.7 (LSAT) substrates by pulsed laser deposition. Real time temperature dependent x-ray diffraction and reflectometry measurements were performed in Pohang accelerator laboratory to redox-driven lattice expansion/reduction. In these real-time x-ray scattering experi-ments, type of ambient gas were only changed between pure N2 and air to check reversibility of the reaction. Additionally, we performed x-ray absorption spectroscopy, spectroscopic ellipsometry, and electronic transport measurements to confirm change of valence states, oxygen contents, and optical bandgap between oxidized and reduced SFCO thin films. The reversible redox reaction in ambient gas condition is another step toward the understanding current and future renewable energy devices.

9:45 AM(EAM-ELEC-S8-025-2018) Tailoring mixed-ionic electronic conductivity in PCO/STO heterostructuresG. Harrington*1; N. H. Perry2; K. Sasaki4; B. Yildiz5; H. L. Tuller3

1. Kyushu Univerisity, Center for Co-Evolutional Social Systems, Japan2. Kyushu University, International Institute for Carbon-Neutral Energy

Research (I2CNER), Japan3. Massachusetts Institute of Technology, Department of Materials Science

and Engineering, USA4. Kyushu University, Center for Co-Evolutional Social Systems, Japan5. Massachusetts Institute of Technology, Department of Nuclear Science

and Engineering, USA

Pr substituted CeO2 (PCO) is an excellent model mixed ionic- electronic conductor (MIEC) for fundamental studies and has potential applications in intermediate temperature electrochemical devices. In high pO2 conditions, vacancy formation is accompa-nied by the reduction of Pr4+ to Pr3+ and the material displays MIEC behaviour via oxygen vacancy migration and small polaron hopping between the valence-active cations. PCO has been extensively studied, and the defect chemistry, chemical expansion, and transport properties are well described in the bulk material. This makes it an excellent choice for studying the interplay of strain, space-charge, and electro-chemo-mechanical coupling effects at heterogeneous interfaces, including their impact on transport properties. We have fabricated multilayer films of alternating Pr0.1Ce0.9O2-d and SrTiO3 (STO) layers using pulsed laser deposition. The nanostructures have been characterised in detail using X-ray diffraction, Raman spec-troscopy, and high-resolution transmission electron microscopy combined with electron energy loss spectroscopy. The conductivity of the layers shows a dramatic weakening of the pO2 dependence as the density of the interfaces is increased, which is consistent with a lowering of the enthalpy for Pr reduction. This study represents an excellent example of the significant potential to tailor the ionic and electronic transport at oxide interfaces.

MagnetismRoom: Orange DSession Chair: Xia Hong, University of Nebraska-Lincoln

10:30 AM(EAM-ELEC-S8-026-2018) Two-Phase Pillars in Nanocomposites Grown by Molecular Beam EpitaxyR. Comes*1; D. E. Perea2; S. Spurgeon2; M. Blanchet1; U. Ubeh1

1. Auburn University, Physics, USA2. Pacific Northwest National Lab, USA

Epitaxial oxide nanocomposites have been explored for many appli-cations, including multiferroic and magnetoelectric properties and catalysis. These nanocomposites form spontaneously during the deposition process of two distinct oxide phases, such as spinels (e.g. NiFe2O4) and perovskites (e.g. LaFeO3). However, there has been little work understanding the energetics that govern the synthesis of these materials—namely, point defect and interfacial energies. To explore these factors, we synthesized La-Ni-Fe-O films by molecular beam epitaxy and showed that they phase segregate into matrix-pillar nanocomposites. Using electron microscopy and atom-probe tomography, we examine the elemental composition of each phase and see that Ni ions are exclusively in spinel pillars. To understand this, we model the favorability of Ni2+ and Ni3+ valences under the growth conditions. We show that multidimensional character-ization techniques provide new insight into the growth process and complex driving forces for phase segregation. We observe a complex microstructure within the pillar that has not been reported in nanocomposites grown by PLD. We see epitaxial inclusions of LaFeO3 within the NiFe2O4 pillar with clear facets that correspond to minimum energy interfaces. These observations indicate that a form of oriented attachment may occur during the growth process, which has not been reported in these nanocomposite systems.

10:45 AM(EAM-ELEC-S8-027-2018) Interface engineering of transition metal oxides as a new route for exploring functional properties (Invited)D. Kan*1

1. Institute for Chemical Research, Japan

Metal-oxygen bonds in transition-metal oxides are responsible for a broad spectrum of functional properties, and atomic-level control of the bonds is a key for developing future oxide-based elec-tronics. Artificial heterostructures with chemically abrupt interfaces consisting of dissimilar oxides have provided a good platform for engineering novel bonding geometries that could lead to emergent phenomena not seen in bulk oxides. Here we show that the Ru-O bonds (or oxygen co-ordination environments) of a perovskite, SrRuO3, can be controlled by heterostructuring SrRuO3 with a thin (0–4 monolayers thick) Ca0.5Sr0.5TiO3 layer grown on a GdScO3 substrate. We found that a Ru-O-Ti bond angle characterizing the SrRuO3/Ca0.5Sr0.5TiO3 interface structure can be engineered by layer-by-layer control of the Ca0.5Sr0.5TiO3 layer thickness, and that the engi-neered Ru-O-Ti bond angle not only stabilizes a Ru-O-Ru bond angle never seen in bulk SrRuO3 but also tunes the magnetic anisotropy in the entire SrRuO3 layer. The results demonstrate that interface engineering of the metal-oxygen bonds is a good way to control additional degrees of freedom in functional oxide hetero-structures. In this talk, I will also show that by applying gate voltages to SrRuO3, its anomalous Hall effect of can be modulated.


Abstracts

11:15 AM(EAM-ELEC-S8-028-2018) Controlling magnetic spin reconstructions by geometrical lattice engineering (Invited)I. Hallsteinsen*1; K. Kjærnes1; M. Moreau1; A. Grutter2; M. Nord3; R. Holmestad3; S. Selbach4; E. Arenholz5; T. Tybell1

1. Norwegian University of Science and Technology, Department of Electronic Systems, Norway

2. National Institute for Science and Technology, Center for Neutron Research, USA

3. Norwegian University of Science and Technology, Department of Physics, Norway

4. Norwegian University of Science and Technology, Department of Material science and engineering, Norway

5. Lawrence Berkeley National Laboratory, Advanced Light Source, USA

Transition metal oxides exhibit strong coupling between atomic structure and magnetic properties, enabling us to engineer epitaxial epilayers with emerging properties at interfaces. One intriguing possibility is to use rotations of the oxygen octhaderal (OOR) to induce new magnetic states, as both exchange coupling and magnetic anisotropy is controlled by the symmetry of the oxygen to transition metal bonds. Here, we present a study of tailoring magnetic proper-ties by imposing different structural symmetries using geometrical lattice engineering, i.e. different strain in the (111)-orientation. As a model system we investigate epitaxial epilayers of antiferromag-netic (AFM) LaFeO3 (LFO) and ferromagnetic (FM) La0.7Sr0.3MnO3 (LSMO). An induced FM moment, ~1.6-2.0 µB/Fe, is found in LFO at the interface with LSMO. No charge transfer is observed, and the effect is attributed to OOR. The induced moment is antiparallel to the moments of LSMO and spans 2-4 Fe-layers. Using a variety of substrates with different crystal symmetries we impose preferen-tial directions to the OOR, which in turn induce an anisotropy to the induced moment, and magnetization reversal. Hence, with the coupled effects of strain, exchange interactions and OOR we can engineer a system with magnetization reversal processes dominated by the FM in the easy direction, and dominated by the AFM in the hard direction.

11:45 AM(EAM-ELEC-S8-029-2018) Multifunctional Oxide-Metal Vertically Aligned Nanocomposite Thin Films (Invited)J. Huang*1; L. Li1; Q. Su3; H. Wang1

1. Purdue University, USA3. University of Nebraska, Lincoln, USA

Heterostructures of metal nanopillars embedded in oxide matrix have attracted tremendous research interests, owing to their nanoscale inclusions and extraordinary properties. To obtain such structures, template or tedious nanofabrication processes are mostly involved. In this work, by precise deposition condition control, one-step thin film growth was used to grow oxide-metal vertically aligned nanocomposite (VAN) thin films on non-tem-plated substrates. Various oxide-metal systems have been achieved, including Au-BaTiO3 (BTO), Ni-BaZr0.8Y0.2O3 (BZY) and Co-BaZrO3 (BZO). Exotic properties were obtained for these unique structures. Anisotropic optical response was achieved for Au-BTO, by angu-lar-dependent and polarization reflectivity measurements, which was further supported by extensive simulation study. Anisotropic magnetic properties were demonstrated for both Ni-BZY and Co-BZO systems, which are promising for the application of high-density perpendicular magnetic storage media.


Materials Design, New Materials and Structures, Their Emerging Applications (I)Room: Orange CSession Chair: Tadej Rojac, Jozef Stefan Institute

8:30 AM(EAM-ELEC-S13-035-2018) Microwave Ceramics: 5G and beyond (Invited)I. M. Reaney*1


The data transmission rates as we move from 4G to 5G and beyond will increase dramatically and ultimately, the materials used in the fabrication of systems and devices will need to make commensurate improvements in dielectric loss and permittivity as well expanding their functionality to keep pace. The drive is to operate at higher frequencies to accommodate the required bandwidth and it is predicted that high Q ceramics will play a major role since dielec-tric loss becomes critical as frequency increases. The presentation will discuss new materials and processes such as ‘cold sintering’ and bespoke multilayer technology that can facilitate greater integration and enhance the functionalty of RF substrates.

9:00 AM(EAM-ELEC-S13-036-2018) Tunable and Multistate Infrared Plasmonics via Ferroelectric Domain ReconfigurationT. E. Beechem*1; M. Goldflam1; M. Sinclair1; D. Peters1; J. Ihlefeld2

1. Sandia National Laboratories, Optical Sciences, USA2. University of Virginia, Department of Materials Science and Engineering,

USA

Tuning optical properties in the long wave infrared (LWIR) has been overwhelmingly dominated by semiconductors where plasmon interactions are modulated by electrostatically induced changes in the carrier concentration. Charge is not the only mechanism by which LWIR properties can be changed, however. Rather, any mechanism by which the dielectric permittivity of the plasmonic medium is affected can be leveraged. Here, lead zirconate titante (PZT) ferroelectric bilayers are instead employed and shown to possess a combination of LWIR tuning advantages—speed, multi-state operation, and scalable feature size—unavailable in approaches demonstrated heretofore. Mechanistically, field-induced domain reconfiguration alters the phonon energies defining PZT’s AC permittivity thereby altering the gap plasmon formed between the ferroelectric and surrounding metals resulting in reflectance changes of ~10% at 800 cm-1 and a multistate unpowered response controlled by the remanent polarization. The utility of ferroelectrics for tunable plasmonics is thus demonstrated. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.


Abstracts

9:15 AM(EAM-ELEC-S13-037-2018) Metal oxide transistors via polyethylenimine doping: Interplay of doping, microstructure, metal cation, and charge transportW. Huang*1; A. Facchetti1

1. Northwestern University, Chemistry, USA

Charge transport and detailed film microstructure evolution are investigated in a series of polyethylenimine (PEI)-doped (from 0% to 6% by weight) amorphous metal oxide (MO) semiconductor thin films. Here, PEI doping capability in binary, ternary and quater-nary systems demonstrates the universality of this approach for electron doping MO matrices. Systematic comparison of the effect of different metal ions on the electron transport and film micro-structure is investigated by a combination of techniques including atomic force microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, X-ray reflectivity, cross-section transmission electron microscopy, and ultraviolet photoelectron spectroscopy. Charge transport measurements in thin-film transistors demonstrate that a peak in charge carrier mobility, and overall performance maximiza-tion, is generally observed for an optimal PEI doping concentration. Optimal PEI loading resulting in the mobility peaks depends not only on the MO elemental composition but, equally important, on the energy level of MO matrices. This work demonstrates the universality of PEI electron doping ability in metal oxide system and that film microstructure, morphology, and energy level are both vital to understanding charge transport in these amorphous oxide blends.

9:30 AM(EAM-ELEC-S13-038-2018) Ultrathin α-Fe2O3 Nanoflakes on TiO2 Nanotubes: Effect of Morphology on Photoelectrocatalytic Water Splitting Hydrogen GenerationH. Han*1

1. Los Alamos National Lab, USA

Large-band gap metal oxide TiO2 have suitable band positions for photoelectrochemical cells (PECs) for solar-driven water splitting, but uses only UV light region in the solar spectrum which repre-sent only about 5 % of the energy. On the other hand, α-Fe2O3 with suitable bandgaps for efficient absorption in the solar spectrum require an external bias to drive hydrogen generation at the cathode due to the conduction band of α-Fe2O3 below the H2 evolution potential and have short carrier diffusion lengths. Synthesizing the metal oxide nanomaterials which have both suitable band position to drive reaction and visible light absorbed band gap is one of the major challenge in PECs for water splitting field. Hetero structure of α-Fe2O3 and TiO2 offer a potential solution to improve this problem. However, the inherent electrical conductivity resulting in the high electron-hole pair recombination rate and short carrier diffusion length of α-Fe2O3 limit its practical use. Here we report a novel hier-archical heterostructure of α-Fe2O3 nanoflakes branched on TiO2 nanotube strategy for PECs for water splitting. On the basis of the detailed experimental results and associated theoretical analysis, we demonstrate that suitable morphological control of α-Fe2O3 and TiO2 plays an important role in enhancing the photoelectrochemical water splitting performance.

9:45 AM(EAM-ELEC-S13-039-2018) Synaptic Plasticity and Metaplasticity Behavior in Ta2O5 Thin film for Artificial Synapse ApplicationsH. Hwang*1; J. Woo1; T. Lee2; S. Nahm2

1. Korea University, Nano-Bio-Information-Technology Converging, KU-KIST Graduate School of Converging Science and Technology, Republic of Korea

2. Korea University, Department of Materials Science and Engineering, Republic of Korea

An artificial synapse based on resistive random access memory (ReRAM) has been investigated for neuromorphic devices.

In this study, memristive amorphous Ta2O5 films were deposited by RF sputtering under 100 °C with 5 mTorr of gas pressure which has Ar:O2 partial pressure ratio of 15:1. Various synaptic func-tions, such as long-term potentiation/depression (LTP/LTD) and spike-timing-dependent plasticity (STDP), were observed in Ta2O5 memristors using a pulse generator. Also, mechanism of synaptic plasticity behavior in Ta2O5 memristors, which originates from oxygen vacancy movements, was studied. Moreover, metaplasticity property, which is higher order form of synaptic plasticity, was investigated by introducing priming stimulus before applying the learning spikes in Ta2O5 memristor.

Characterization of Materials II: Crystal Structure and PropertiesRoom: Orange CSession Chairs: Jun Chen, University of Science and Technology Beijing; Brian Foley, Georgia Institute of Technology

10:30 AM(EAM-ELEC-S13-040-2018) Origin of High Performance Piezoelectrics of Pb-Based Perovskites (Invited)J. Chen*1; L. Fan1; H. Liu1; Y. Ren2; X. Xing1

1. University of Science and Technology Beijing, Department of Physical Chemistry, China

2. Argonne National Lab, X-ray Science Division, USA

The studies on high performance mechanism remain debate, such as MPB, monoclinic phase, and nanodomains. Revealing the piezoelec-tric mechanism is a key point for the development of piezoelectric materials. The main obstacle for the mechanism study is the problem of electric field introduced strong texture. In this work, we have performed in-situ high-energy X-ray diffraction combined with 2D geometry scattering technology to reveal the underlying mechanism for the perovskite-type Pb-based high-performance piezoelectrics. The present in-situ method can simultaneously obtain crystal struc-ture, phase content, lattice strain, and domain switching as function of electric field. Firstly, a single monoclinic phase has been identified in PZT at room temperature. Unique piezoelectric properties of the monoclinic phase in terms of large intrinsic lattice strain and negli-gible extrinsic domain switching have been observed. Secondly, the direct structural evidence has revealed that the electric-field-driven continuous polarization rotation within the monoclinic plane plays a critical role to achieve the giant piezoelectric response. An intrinsic relationship between crystal structure and piezoelectric performance in perovskite ferroelectrics has been established.

11:00 AM(EAM-ELEC-S13-041-2018) Intrinsic and Extrinsic Influences on Phonon Thermal Transport Processes in Electronic Materials (Invited)B. Foley*1

1. Georgia Institute of Technology, George W. Woodruff School of Mechanical Engineering, USA

While much of the excitement surrounding new and/or novel materials is often centered on its electrical or optical properties, the thermal properties are often overlooked in the early stages of the development process. As these thermal properties can have a profound impact on the operational performance of the mate-rial/device, a better approach would be to employ electro- and/or opto-thermal co-design early in the design/discovery process. This presentation will focus on the characterization of thermal transport processes in a variety of material systems, with particular attention towards the role of both structure and size-effects on phonon-dom-inated thermal transport. A variety of structure-property relationships related to thermal transport will be explored, including octahedral-distortions in various perovskites (oxides and halides), phonon scattering at coherent interfaces such as ferroelastic domain


Abstracts

boundaries in BiFeO3, and phonon transport in solid-solutions such as PZT. In addition, the impact of applied electric fields on thermal properties will be explored, including the modulation of phonon thermal flux through ferroelastic domain wall generation/annihila-tion, as well as field-induced phase transitions. The overarching goal of this presentation is to provide attendees with an improved under-standing of phonon thermal transport which can be applied in their research.

11:30 AM(EAM-ELEC-S13-042-2018) Pump-probe measurements of Vanadium dioxide above and below the bandgapE. Radue*1; S. Kittiwatanakul1; P. E. Hopkins1

1. University of Virginia, Mechanical and Aerospace Engineering, USA

Vanadium Dioxide is a highly correlated material that undergoes a first order insulator-metal transition when heated past 340 K, with a 105 order change in electrical conductivity and an ultrafast insu-lator-metal transition, making it an attractive material for ultra-fast switches and passive thermal switches. While this transition is characterized by both a change in band structure and a change in lattice symmetry, it is still unclear whether the VO2 transition is primarily a Mott transition, a Peierls transition, or a combination of both. Understanding this transition is important to engineering and tailoring VO2 nanomaterials. We are examining several samples of VO2 films grown on different substrates (with different transition temperatures) in a pump-probe experimental set-up, with a 520 nm pump and a tunable probe beam ranging from 1100 nm to 2600 nm. We are measuring the dynamics above and below the bandgap of VO2 films as we pump the films above the transition temperature, and exploring how the electronic response differs as we scan across the bandgap.

11:45 AM(EAM-ELEC-S13-043-2018) Identifying the fundamental mechanisms that limit the performance of modern microwave ceramicsN. Newman*1; A. Sayyadishahraki2; J. Gonzales1

1. Arizona State University, Materials Program, USA2. Tarbiat Modares University, Department of Materials Science and

Engineering, Islamic Republic of Iran

Miniaturization of microwave systems require low-loss tempera-ture-compensated ceramics with large dielectric constants. Despite the practical importance of achieving a small loss tangent (tan δ) and near-zero temperature coefficient of resonant frequency (τF), a fundamental understanding of the mechanisms respon-sible for determining them haven’t been established. I focus on my group’s efforts using modern experiments and theory to identify the responsible mechanisms in practical materials. In one example, I show that the properties of commercial cell-phone base station filters, are improved by adding dopants or alloying agents, such as Ni or Co, to Ba(Zn1/3Ta2/3)O3 and Ba(Zn1/3Nb2/3)O3 to adjust τF to zero. This occurs as a result of the temperature dependence of εrµr offsetting the thermal expansion. We will show that the dominant loss mechanism in these commercial materials comes from spin excitations of unpaired transition-metal d electrons in exchange coupled clusters, particularly at reduced temperature. I will high-light how the development of this understanding has allowed us to engineer magnetic-field tunable ultra-high Q dielectric microwave resonators and filters. In another example, we show how the manu-facturer’s use of non-stoichiometric compounds reduces microwave loss through the reduction of the native defects responsible for performance-killing polaron transport.

12:00 PM(EAM-ELEC-S13-044-2018) Probing the trap levels in the wide band gap TiO2 by Deep Level Transient SpectroscopyA. Kumar*1; S. Mondal2; G. Aman3; K. Rao2

1. Indira Gandhi National Tribal University, Amarkantak, MP, INDIA, Department of Physics, India

2. Indian Institute of Science, Department of Physics, India3. University of Cincinnati, Department of Electrical Engneering, USA

TiO2 is an important material due to the application in various fields of science and technology, including medicine. However, it suffers from the enormous amount of native defects. Moreover, many of the interesting properties such as resistive switching, intrinsic n-type conductivity are governed by these. Hence, the truthful under-standing of these defects will be essential and provide an insight to design the new devices based on TiO2. In this, work we have fabri-cated TiO2 thin film based Metal - Oxide - Semiconductor (MOS) capacitor to study the deep defects present in wide band gap TiO2 by Deep Level Transient Spectroscopy (DLTS) method. We have preferred MOS capacitor instead of p-n junction as the fabrication of TiO2 based p-n junction is very difficult. Whereas, MOS capacitor is an important component of CMOS technology and DLTS investiga-tion on it provide all the information associated with defects which we can obtain with the p-n junction. The analysis reveals five peaks in DLTS spectrum and in light of theoretical reports; we believe these are belonging to the oxygen vacancies and Ti interstitial related defects. These defects levels are located at 0.66 – 1.07 eV below the conduction band edge of TiO2. The capture cross-sections and defect densities are in the range of 4.3×10-17 – 3.2×10-19 cm2 and 1.9×1014 – 2.7×1016 cm-3, respectively.

12:15 PM(EAM-ELEC-S13-045-2018) Engineering ferroelectric domain architectures in PbTiO3 thin filmsE. Langenberg*2; N. Domingo1; E. Smith2; H. Nair2; H. Paik2; G. Catalan1; D. Schlom2

1. Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC, Barcelona Institute of Science and Technology, Spain

2. Cornell University, Department of Materials Science and Engineering, USA

The ability to engineer ferroelectric domain configurations at will can boost the developement of new functionalities in which ferro-electric domains and domain walls play a central role. Here we use strain engineering to design different domain architectures and to provide experimental evidence of the strain-ferroelectric domain phase diagram in PbTiO3. Reactive Molecular-Beam Epitaxy is used to grow high-crystalline-quality PbTiO3 films, in a layer-by-layer growth, on several single crystal perovskite substrates, namely, SrTiO3, DyScO3, GdScO3, SmScO3, PrScO3, spanning from -1.36% compressive strain to +1.54% tensile strain. Our results show that for large compressive strain pure c-domains PbTiO3 thin films are obtained. On reducing the compressive strain, a gradual increase of the presence of a-domains embedded in a c-domain matrix takes place, giving rise to a/c domain architectures. At low/moderate tensile strains a competing scenario of a/c and a1/a2 domain config-urations are found, the ratio of which can be tuned by both strain and thickness. At large tensile strains, a new phase seems to be found: orthorhombic aa-domains with the polarization along the [110] direction. In summary, we show here a thorough review of all possible ferroelectric domain architectures that are accessible in PbTiO3 thin films and how to switch between them by selecting the epitaxial strain and thickness appropriately.


Abstracts


Data Science and High-throughput Approaches IIRoom: Citrus BSession Chair: Ming Tang, Rice University

2:00 PM(EAM-JOINT-009-2018) Enhancing agile chemical selection for multifunctional ceramic through informatics (Invited)K. Rajan*1

1. University at Buffalo: the State Univ. of New York, Materials Design and Innovation, USA

This presentation will provide and overview of computational strat-egies that harness statistical learning methods for the selection and design of crystal chemistry for multifunctional ceramics such as ferroelectrics and related classes of materials. We show how data driven methods can identify new parameters and new correlations that can help to guide experimental design of new materials. The discussion will focus on one can harness the tools of data dimension-ality reduction to rapidly identify chemical pathways for materials design.

2:30 PM(EAM-JOINT-010-2018) High-Throughput Computational Studies of Two-Dimensional Transition Metal DichalcogenidesL. Li*1

1. Boise State University, Micron School of Materials Science and Engineering, USA

In order to quickly and effectively identify the best candidates for desired electronic applications, we need to generate large and rich structural and property data through high-throughput compu-tational screening based on first-principles calculations. This presentation will demonstrate our newly developed screening methods applicable to two-dimensional transition metal dichalco-genides (2D-TMDs) for tunnel field-effect transistor applications. TMD has the chemical formula MX2. M refers to a transition metal while X is a chalcogen. Many TMD combinations are possible. We combined first-principles approaches, Boltzmann transport theory, and refined atomistic Green’s function to screen the structures, elec-trical, phonon and thermal properties of approximately 200 TMD compounds, including pristine, doping, and heterostructuring. We found that atomic weight, radius, oxidation state and interfacial lattice mismatching control the properties.

2:45 PM(EAM-JOINT-011-2018) Functional Defects by Design: A High-Throughput Approach to Energy Materials Discovery (Invited)P. Ganesh*1


Defects and impurities introduce localized heterogeneities in solids and decisively control the behavior of a wide range of energy tech-nologies. Fuel cell materials, especially proton conducting fuel cells, are a quintessential example in this regard. We initially focus on the perovskite family of compounds (such as doped BaZrO3). We benchmark our ab initio calculations against a wide range of experimental measurements such as kelvin probe force micros-copy (KPFM), scanning transmission electron microscopy (STEM), inelastic neutron scattering (INS) and atom probe tomography (APT). To obtain better insights on why certain cubic perovskite/dopant combinations are better at conducting protons compared to others, we developed a high- throughput framework to perform scal-able ab initio calculations on the Titan supercomputer. We employ this approach to calculate proton transport properties in several cubic perovskite materials with different host atoms and dopants.

The results obtained from these calculations enables us to obtain better insights on how material structure – such as atomic properties (electronegativity, ionic radius) and lattice properties (sub-lattice polaronic distortion) influences proton transport. Based on this insight, we rationally come up with a design criteria to improve proton conduction in perovskite oxides.

3:15 PM(EAM-JOINT-012-2018) High Throughput Scanning Probe Microscopy of Multiferroic Thin Film PropertiesJ. Steffes1; P. Ashby2; R. Cordier1; B. Huey*1

1. University of Connecticut, Institute of Materials Science, USA2. LBNL, Molecular Foundry, USA

Pizeoresponse force microscopy (PFM), a variant of AFM, is often used to measure domain configurations and track switching for ferroelectrics. We report PFM on multiferroic BiFeO3 with high temporal and spatial density, yielding datasets of 500 million points i.e. 4 orders of magnitude larger than a standard image. This is based on high-speed PFM at several frames per second, recording sample topography simultaneously with the in-plane and out-of-plane piezoresponse to monitor polarization dynamics during multiple switching cycles. To track domain evolution through these cycles, unique metrics must be employed including quantifying static domain boundaries as well as dynamics such as local domain wall velocities. Temporal sub-sampling and unique process identifiers improve the efficiency of identifying important signals in these >1000 image datasets. PFM and simultaneous conductive-probe AFM (CAFM) measurements are also reported for BiFeO3 cross-sec-tions to generate through-thickness maps of domain orientation and conductivity. To assist in the visualization and quantification of these coupled functional properties, Fourier analysis, image filtering, and multi-parametric image rendering can be employed. Such novel, multi-dimensional, high data density investigations are critical for correlating microstructure with multiferroic properties.

3:30 PM(EAM-JOINT-013-2018) Towards Efficient Optoelectronic Material Design using Density Functional Theory, Experiments and Machine LearningK. Choudhary*1

1. National Institute of Standards and Technology, MML, USA

We present an open access computational database for optoelec-tronic properties of materials using density functional theory. Fundamental electronic bandgaps and frequency dependent dielec-tric functions are obtained with OptB88vDW (OPT) functional and Tran-Blaha modified Becke Johnson potential (MBJ). At present, we have 10513 OPT and 4035 MBJ bandgaps and dielectric functions. A subset of bandgap data is compared to experiments. We also carry out ellipsometry experiments to validate some of our dielectric func-tion data. MBJ functional is found to predict better bandgaps than OPT, so it can be used to improve the well-known bandgap problem of DFT in a relatively inexpensive way. The peak positions in dielec-tric function and refractive index data obtained with OPT and MBJ are in comparable agreement with experiments. We use this data to train a machine learning model to predict the bandgap of any material at very low computational cost. The data is available at our website: http://www.ctcms.nist.gov/~knc6/JVASP.html.


Abstracts


Growth and Characterization of OxidesRoom: Citrus ASession Chair: Abhinav Prakash, University of Minnesota

2:00 PM(EAM-ELEC-S1-021-2018) Highly Stoichiometric SrTiO3 Thin Films Grown via Metal-organic Pulsed Laser Deposition (Invited)J. Lee*1; A. L. Edgeton1; N. Campbell2; H. Lee1; B. Noesges3; T. R. Paudel4; J. L. Schad1; Y. Ma1; E. Y. Tsymbal4; L. J. Brillson3; D. A. Tenne5; M. Rzchowski2; C. Eom1


2. University of Wisconsin-Madison, Physics, USA3. Ohio State University, Physics, USA4. University of Nebraska, Lincoln, Physics and Astronomy, USA5. Boise State University, Physics, USA

Pulsed laser deposition (PLD) has been widely used for fabri-cation of complex oxide thin films and their heterostructures. However, a precise control of cation stoichiometry in complex oxide thin films to obtain bulk single crystal properties is chal-lenging due to the non-equilibrium nature of PLD growth. Here, we demonstrated highly stoichiometric SrTiO3 thin films via a near-equilibrium synthesis technique, metal-organic pulsed laser deposition (MOPLD) where titanium tertaisopropoxide (TTIP) is used as a Ti source during the laser ablation of a SrO target. X-ray diffraction and Raman spectroscopy confirm there is a stoichio-metric SrTiO3 growth window for a wider flux range of TTIP. By comparing electronic properties of the two dimensional electron gas at LaAlO3/SrTiO3 interfaces, we demonstrated that the quality of SrTiO3 films grown via MOPLD is comparable to bulk single crystal SrTiO3. The relationship among stoichiometry, point defects in SrTiO3 films, electrical properties of LaAlO3/SrTiO3 interfaces will be discussed.

2:30 PM(EAM-ELEC-S1-022-2018) Atomic and electronic structure of point, line, and planar defects in perovskite oxides (Invited)J. Jeong*1; H. Yun1; M. Topsakal1; P. Xu1; A. Prakash1; B. Jalan1; A. Mkhoyan1

1. University of Minnesota, Chemical Engineering and Materials Science, USA

Perovskite oxides have demonstrated remarkable properties, in the form of bulk, interfaces, or heterostructures, such as room-tem-perature ferroelectricity, giant piezoelectricity, quantum oscillation, two-dimensional superconductivity, etc. The chemical diversity, stability under off-stoichiometry, and variety of crystal symme-tries in the perovskite structure make it a natural host for a range of defects as well. The role played by defects in the basic proper-ties of materials cannot be overstated, and it is critical to control such defects for future application. Here atomic-resolution analyt-ical scanning transmission electron microscopy is used to study the local atomic and electronic structure of point, line, and planar defects of perovskite oxides including doped SrTiO3, BaSnO3, and NdTiO3. Strain analysis using annular dark-field images and simu-lation allows us to directly detect the interstitials in SrTiO3 film and to identify their valence state. Various Ruddlesden-Popper defects were analyzed using atomic-resolution electron energy-loss spec-troscopy and electron dispersive x-ray spectroscopy. We also report the detailed analysis of the inner structure of a novel line defect in

NdTiO3. We suggest that this new line defect could be a building block for planar defects like Ruddlesden-Popper defect, which can give us a clue to link the transition from point defects to planar defects.

3:00 PM(EAM-ELEC-S1-023-2018) A Semiconductor/VO2 Hybrid (Invited)Y. Wang1; J. Shi*1

1. Rensselaer Polytechnic Institute, USA

While strain engineering has long been considered an effective way to edit semiconductor properties, strategy to dynamically control strain and therefore physical properties remains limited due to the relative insensitivity of semiconductors’ electron-lattice response on environmental perturbations. We suggest a dynamic approach of strain engineering that takes advantage of the colossal strong correlation effect in VO2 micron beams. By triggering the metal- insulator phase transition in VO2 via temperature, we translate the strain and strain patterns from VO2 to the wurtzite semiconductor CdS, which in turns leads to the modulation of CdS’s electron-lattice interactions. As a result, CdS’s band structure is engineered being a first-order nonlinear function of temperature. Our finding agrees well with the prediction via deformation potential theory and k∈p method. For the first time, it suggests strong correlation effect in strongly correlated oxides could be very promising as new approach for effective strain engineering. It may outperform several other approaches in terms of dynamicity and manipulability since any perturbation (temperature, electric field, pressure) that could trigger phase transition in strongly correlated oxides could lead to property modulations in the as-grown semiconductors.

3:30 PM(EAM-ELEC-S1-024-2018) Pathway to p-type doping of metal-oxide semiconductorsF. P. Sabino*1; A. Janotti1


Metal-oxide semiconductors form a large class of materials with high technological importance for a wide range of applications, including transparent contacts for solar cells and LEDs, transparent transistors, and water splitting. In general, oxide semiconductors display n-type conductivity which is associated with a typically low-energy conduction-band-minimum with respect to vacuum, i.e., high electron affinity. In addition, most of the impurities are shallow donors, easily giving up an electron to the conduction band. Making oxide semiconductors p-type, in contrast, is quite challenging, though highly desirable for many applications. The valence band in oxides, composed mainly by oxygen p-orbitals, is quite low with respect to vacuum, which translates into very high ionization poten-tials. Besides compensation by native donor defects, the hole in the valence band in this class of oxides has a tendency for self-trapping, becoming localized in the form of a small polaron, accompanied by a local lattice distortion. Using density functional calculations based on the Heyd-Scuseria-Ernzerhof (HSE) hybrid functional, we explore the relation between the local lattice distortions associated with the localized hole due to an acceptor impurity and the position of the acceptor transition level in the gap of SrTiO3 and TiO2. Our results open a path to p-type doping in this class of materials.


Abstracts


Functionalities: ElectronicRoom: Orange DSession Chair: Ryan Comes, Auburn University

2:00 PM(EAM-ELEC-S8-030-2018) Origin of Gap State Photoemission in n-SrTiO3(001) (Invited)S. Chambers*1

1. Pacific Northwest National Laboratory, Physical and Computational Sciences Directorate, USA

SrTiO3 (STO) is a prototypical oxide semiconductor of considerable current interest. Bulk STO crystals have been used for years as both the substrate and an active ingredient in oxide heterostructures. For instance, there are by now over 1000 papers on the LaAlO3/SrTiO3 (LAO/STO) heterojunction in which conductivity is activated in STO by the deposition of LAO. The top few nm of the STO substrate constitute the channel in LAO/STO based devices. As STO is doped n-type, several photoemission studies have noted the presence of one feature near the Fermi level (the “metallic band”) and a broader feature deeper in the gap (the “in-gap state”). The same is true when bulk STO(001) surfaces are irradiated with a synchrotron beam; a two-dimensional electron gas forms as O vacancies are created and the same two bands appear. While the metallic band intensity scales with the donor concentration, the origin of the in-gap state(s) is less clear. Proposed explanations range from correlation effects to a splitting off from the metallic band, leading to localized states. All explanations offered to date involve intrinsic effects. We have carried out a study aimed at identifying the physical cause of the in-gap state in Nb:STO(001) specimens. Our results point to Sr vacancies. These deep-level acceptors trap electrons from Nb donors. In this talk, I will present spectroscopic evidence for this conclusion.

2:30 PM(EAM-ELEC-S8-031-2018) Application of metamaterial nano-engineering for increasing the superconducting critical temperature (Invited)M. Osofsky*1; V. Smolyaninova2; T. Gresock2; S. Saha3; B. Yost2; C. Jensen2; J. Prestigiacomo1; H. Kim1; N. Bassim5; R. Greene3; I. Smolyaninov3

1. Naval Research Laboratory, USA2. Towson University, USA3. University of Maryland, USA5. McMaster University, Canada

We have demonstrated that the metamaterial approach to dielec-tric response engineering increases the critical temperature of a composite superconductor-dielectric system in the epsilon near zero (ENZ) and hyperbolic regimes. To create such metamaterial superconductors three approaches were implemented. In the first approach, mixtures of tin and barium titanate nanoparticles of varying composition were used. An increase of the critical tempera-ture of the order of 5% compared to bulk tin has been observed for a 40% volume fraction of barium titanate nanoparticles. Similar results were also obtained with compressed mixtures of tin and strontium titanate nanoparticles. In the second approach, we demonstrate the use of Al2O3-coated aluminium nanoparticles to form an ENZ core-shell metamaterial superconductor with a Tc that is three times that of pure aluminium. In the third approach, we demonstrate a similar Tc enhancement in thin Al/Al2O3 heterostructures that form a hyper-bolic metamaterial superconductor. IR reflectivity measurements confirm the predicted metamaterial modification of the dielec-tric function thus demonstrating the efficacy of the metamaterial approach to Tc engineering.

3:00 PM(EAM-ELEC-S8-032-2018) Tuning the Plasma Frequency in Correlated Transition Metal Oxides (Invited)T. Birol*1

1. University of Minnesota, USA

Transparent conductors, materials that bring together electrical conductivity with optical transparency, are usually designed starting with a wide transparent insulator, which is then doped to intro-duce charge carriers. However, this approach is often limited in the maximum conductivity that can be obtained because of both defect scattering and doping bottlenecks. An alternative approach is to design a metal that has weak interband absorption and a plasma frequency that is suppressed below the visible spectrum. Design principles that employ different features in the band structure, as well as electronic correlations have been put forward. We present a systematic first principles study of the effect of biaxial strain, octahedral rotations, and layering on the transparent conducting properties of d1 perovskites. We employ Denstiry Functional Theory in conjunction with Dynamical Mean Field Theory (DFT+DMFT) to predict the correlation induced suppression of the plasma frequency and show that it can be significant even in the 4d transition metal oxides. We show that factors such as polyhedral connectivity induce changes much more significant than strain or octahedral rotations in weakly correlated oxides.

Functionalities: ElectrochemicalRoom: Orange DSession Chair: Abhinav Prakash, University of Minnesota

4:00 PM(EAM-ELEC-S8-033-2018) Self-assembled metal nanopillars embedded in oxide semiconductor photoelectrode for photoelectrochemical water splitting (Invited)R. Takahashi*1

1. Institute for Solid State Physics, University of Tokyo, Japan

Production of hydrogen gas by direct solar energy conversion in a photoelectrochemical cell is one possible technique for devel-oping a sustainable energy system. Nanostructure designs have been investigated to enhance the energy conversion efficiency of photoelectrochemical water splitting electrodes. Here, we have demonstrated a self-organized nanocomposite photoelectrode to increase the efficiency of photocarrier separation and electro-chemical energy conversion. Self-assembled metal nanopillars in a semiconductor thin film were found to form tubular Schottky junctions around each pillar and strongly enhance the photocar-rier transport efficiency. Ir-doped SrTiO3 with embedded Ir metal nanopillars exhibits good operational stability in a water oxidation reaction and high energy conversion efficiency.

4:15 PM(EAM-ELEC-S8-034-2018) Cathode/electrolyte nanocomposite films for enhanced 3D solid-state batteriesM. Huijben*1

1. University of Twente, Netherlands

The successful application of all-solid-state batteries depends strongly on the enhancement of energy density and lifetime, which are dependent on the nature of the interfaces between the electrodes and electrolyte. Mastering control of these interfaces is identified as a grand challenge in battery research, being more important than designing new electrode and electrolyte materials. To increase the volumetric energy and power densities, 3D battery geometries can be applied. Self-assembled vertically aligned nanocomposite thin films have been grown by us for the first time for battery applica-tions to create electrode/electrolyte nanocomposites, consisting of two immiscible perovskite/spinel phases. A promising high voltage


Abstracts

cathode material is the spinel LiMn2O4, while a promising electrolyte material is the perovskite LixLa1-xTiO3, where the partially occu-pied Li and La sites provide an interconnected pathway for lithium migration. We have studied LiMn2O4 - LixLa1-xTiO3 nanocomposite thin films, which have been grown by PLD on conducting Nb-doped SrTiO3 substrates with different crystal orientation ((001), (111) and (110)). As the crystal structure of the electrode nanopillars, electrolyte matrix and their interfaces will determine the lithium diffusion mechanism, variations have been applied to the size and orientations of the crystal structures to characterize the relationship between them.

4:30 PM(EAM-ELEC-S8-035-2018) Three-Dimensional Nanostructured Oxides Heterostructures for Enhanced Photoelectrochemical PerformanceI. Choi1; H. Jeong1; J. Kim*1

1. Pohang University of Science and Technology(POSTECH), Materials Science and Engineering, Republic of Korea

Three-dimensional nanostructured oxides thin films materials fabricated by electron-beam oblique-angle deposition and their application for photo-electrodes in photoelectrochemical (PEC) cells are presented. A helical WO3 array was fabricated, followed by subsequent coating with BiVO4 to form a heterojunction. The combination of effective light scattering, improved charge separa-tion and transportation and an enlarged contact surface area with electrolytes due to the use of the BiVO4-decorated WO3 helical nanostructures led to the photocurrent density of approximately 5.35 mA/cm2 was achieved at 1.23 V versus the reversible hydrogen electrode. In addition, we demonstrated a simple yet highly effec-tive hybrid conductive distributed Bragg reflector that functions as both an optical filter as well as a counter-electrode for the rear dye-sensitized solar cell for a tandem cell configuration. The hybrid conductive distributed Bragg reflectors were designed to be trans-parent to the long-wavelength part of the incident solar spectrum for the rear solar cell, while reflecting back the short-wavelength photons which can then be absorbed by the front photoelectrochem-ical electrode for enhanced photocurrent generation.

4:45 PM(EAM-ELEC-S8-036-2018) Tuning the Electronic Structure of NiO by Li doping for Electrocatalytic Water Oxidation (Invited)K. H. Zhang*1

1. Xiamen University, College of Chemistry and Chemical Engineering, China

Earth-abundant transition metal (TM) oxides are excellent mate-rials as electrocatalysts for oxygen evolution reaction (OER). It has been proposed that similar to the d-band theory in metal catalysts, the intrinsic OER activity of TM oxides is strongly linked with their electronic structures, i.e., transition metal cations with an occupa-tion of eg=1 showing a high OER activity. This provides guideline for rational design of electrocatalysts. We have synthesized Li doped NiO (LixNi1-xO, x= 0, 0.09, 0.17, 0.33 and 0.5) powders and found the mate-rials show increasing catalytic activity for OER as x increases, with comparable OER activity to that of precious IrO2 when x=0.5. The dependence of structure and electronic properties on composition were systematically investigated using high-resolution X-ray photo-emission spectroscopy (XPS) and X-ray absorption (XAS), and density functional theory (DFT) calculations. NiO is a wide bandgap (Eg=3.6 eV) semiconductor with a nominal charge state of Ni2+ (eg2), while Ni in the other end member Li0.5Ni0.5O has a nominal charge state of Ni3+ (eg1). O-K edge XAS indicates development of unoccupied states at 0.5 eV above the top of valence band (VB) with increasing Li doping. These experimental results supplemented with DFT calculations established a direct correlation between the enhancement of catalytic activity with the change of electronic structure.


Materials Design, New Materials and Structures, Their Emerging Applications IIRoom: Orange CSession Chair: Ian Reaney, University of Sheffield

2:00 PM(EAM-ELEC-S13-046-2018) Dynamics of Conducting Domain Walls in Polycrystalline BiFeO3 and its Effect on Macroscopic Electrical and Electromechanical Properties (Invited)T. Rojac*1; A. Bencan1; H. Uršič1; B. Jancar1; M. Makarovic1; A. Bradesko1; B. Malic1; G. Drazic3; L. Liu4; J. Daniels4; D. Damjanovic2

1. Jozef Stefan Institute, Electronic Ceramics Department, Slovenia2. Swiss Federal Institute of Technology in Lausanne - EPFL, Ceramics

Laboratory, Switzerland3. National Institute of Chemistry, Laboratory for Materials Chemistry,

Slovenia4. University of New South Wales, School of Materials Science and

Engineering, Australia

Domain walls (DWs) are dynamic interfaces contributing domi-nantly (>50%) to the macroscopic piezoelectric response of polycrystalline ferroelectrics. Only recently, however, it has been demonstrated that DWs can exhibit their own properties, such as elevated electrical conductivity, making the local-global proper-ties relationship even more complex. Two key questions open up: i) which is the mechanism governing the DW conductivity and ii) how does this conductivity affect DW dynamics and macroscopic piezoelectric properties? In this contribution, we will show that DWs in polycrystralline BiFeO3 tend to accumulate charged defects during the aging period. Using atomic-resolution microscopy we identify the defects as Bi vacancies and Fe4+ states, explaining the p-type (Fe4+-related) electrical conduction at DWs. Domain switching studies and analyses of the piezoelectric response as s function of driving field parameters and temperature suggest that the local conductivity has a marking effect on the macroscopic properties of BiFeO3. The particular piezoelectric behavior, such as strong enhancement of nonlinear hysteretic response at low frequen-cies and negative phase angle, arising from conducting DWs, is confirmed by in-situ X-ray diffraction studies.

2:30 PM(EAM-ELEC-S13-047-2018) Oxygen deficient gadolinium doped ceria as colossal dielectric constant and varistor thin film materialM. Hadad1; P. R. Muralt*1

1. EPFL, Materials Science and Engineering, Switzerland

The discovery of giant electrostriction (GES) in thin films of Gd doped ceria raised the question of dielectric anomalies, because high electrostriction in inorganic materials is linked to high dielec-tric constants. We have shown that the GES effect in Ce0.8Gd0.2O2-x thin films is quite slow, typically limited to below 1 kHz, and that it is due to additional oxygen vacancies caused by reducing process conditions during film deposition. Such additional vacancies are compensated by the formation of Ce3+ ions with an occupied 4f state, forming small polarons, which propagate by hopping. Our experiments showed that GES films exhibited very high dielectric constants of over 1000. Dielectric spectroscopy reveals a Maxwell-Wagner relaxation due to a series RC element, formed by the combination of strong leakage through the bulk with an acti-vation energy of 0.51 eV, and an interface barrier layer. A strong universal dielectric relaxation behavior is observed. The interface layer is formed by post-oxidation in case of Pt electrodes, and by


Abstracts

oxide scale formation in case of Al bottom electrodes. Conduction through the interface layers is controlled by higher activation ener-gies (1.2 eV), leading varistor-type IV-curves. All these features recall very much colossal dielectric constant materials such as CaCu3Ti4O12 thin films.

2:45 PM(EAM-ELEC-S13-048-2018) Transparent Heteroepitaxy (Ba, La)SnO3/Muscovite for Flexible OptoelectronicsC. Yang*1; M. Yen1; K. Kim2; Y. Chu1

1. National Chiao Tung University, Materials Science and Engineering, Taiwan

2. Seoul National University, Physics and Astronomy, Republic of Korea

Over the past decade, there have been dramatic technological advances in portable electronics, flexible electronics, multifunctional windows, and numerous other devices that feature transparent electrodes. Transparent conducting oxides (TCO) have served as fundamental components in advanced optoelectronic devices spanning solar cells, light emitting diodes, thin film transistors, photocatalysis, flat panel displays, and energy efficient windows. As there is an increasing demand in next-generation devices with high performance, improving the mobility is an essential issue for devel-oping transparent logic devices. Lanthanum-doped barium stannate (Ba, La)SnO3 (BLSO) is a new TCO with high electron mobility in perovskite structure which captured significant attention in the last decade. In this study, we intend to grow BLSO thin film heteroep-itaxially on flexible transparent mica substrates by pulsed laser deposition (PLD) process to achieve the flexible TCO with the elec-tron mobility higher than 100 cm2/(Vs). The combination of BLSO and muscovite exhibits not only excellent electrical properties but also optical and flexible characteristics. This offers a pathway to fabricate flexible transparent high-power functional devices for optoelectronic applications.

3:00 PM(EAM-ELEC-S13-049-2018) Dependence of leakage on polarization and its implications for resistive switchingB. Misirlioglu*2; O. M. Moradi2; C. M. Sen2; L. Pintilie1; A. Boni1

1. NIMP, Romania2. Sabanci University, Faculty of Engineering and Natural Sciences, Turkey

In this work, we present on the variability of the Schottky effect in Ba1-xSrxTiO3 films (BST, x=0, 0.5) grown on 0.5% Nb doped SrTiO3 substrates with top Pt electrodes (NSTO/BST/Pt). Films show leakage accompanied by varying degrees of hystereses in the current-voltage (I-V) measurements along the film normal depending on Sr content. We focus on I-V behavior of our samples in the light of thermodynamic theory coupled with equations of semiconductors, allowing us to unambigously determine the electronic character of the defects and related band bending effects in our samples. The extent of asymmetry and the hystereses in the I-V curves are shown to be controlled by the polarization induced interface effects. Amplitude of the ferroelectric polarization, which is a function of composition here, has a strong impact on leakage currents in forward bias while this effect is much weaker under negative bias. The latter occurs as any non-zero polarization pointing away from the NSTO substrate causes depletion of carriers at the NSTO side of the NSTO/BST interface. Such an occurence increases the energy gap between the Fermi level and the conduction band, thereby also reducing the bulk conduction through the film. Dependence of leakage currents on polarization direction points out to the possi-bility of a non-destructive read-out route in ferroelectric films much thicker than tunnel junctions.

3:15 PM(EAM-ELEC-S13-050-2018) Detailed Investigation of Thermoelectric Properties of A-site Doped Sr2TiMoO6 Based Double PerovskitesM. Saxena*1; T. Maiti1

1. Indian Institute of Technology Kanpur, Materials Science and Engineering, India

Recently double perovskites (A2B/B//O6) have been investigated as thermoelectric materials due to good combination of high Seebeck coefficient, good electrical conductivity and low thermal conduc-tivity. In general, double perovskite materials show high Seebeck coefficient, however they suffer from low electrical conductivity. Electrical conductivity of these materials needs to be improved to develop efficient thermoelectric devices. In the present work, envi-ronment friendly, non-toxic double perovskites AxSr2-xTiMoO6 (A=Ba, La) have been synthesized by solid-state reaction process. Sintering of these ceramics has been done under reducing atmo-sphere to obtain single phase compound. The electrical conductivity and Seebeck coefficient were simultaneously measured from room temperature to 1273 K. Thermopower (S) measurement confirmed the conductivity switching from p-type to n-type behaviour at higher temperature. XPS measurement has been carried out to eval-uate the source of charge carries and oxidation states of cations in these ceramics. Conductivity mechanism of these double perovskites has been found to be governed by small polaron hopping model. Temperature dependent Seebeck coefficient has been explained using an analytical model for coexistence of low mobility oxygen vacancies and high mobility electrons in these oxides.

Author Index* Denotes Presenter


AAbernathy, D.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Acosta, M.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Agarwal, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63Ahn, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75Aigner, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Aimi, A.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67Akama, A.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Akkopru Akgun, B.* . . . . . . . . . . . . . . . . . . . . . . . 16Al-Aaraji, M. N.* . . . . . . . . . . . . . . . . . . . . . . . . . . 35Al-Hamed, F. H.* . . . . . . . . . . . . . . . . . . . . . . . . . 36Alamgir, F. M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 42Albe, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73Alem, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Alpay, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . 12, 36, 46Alpay, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46Altermann, F. J. . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Altermann, F. J.* . . . . . . . . . . . . . . . . . . . . . . . . . . 11Aman, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78An, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37An, L.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40An, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Anand, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50Anderson, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Anusca, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Arenholz, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . 25, 76Arroyave, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68Asel, T. J.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55Ashby, P.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79Ashton, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35, 59Aslam, Z.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Asmara, T. C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49Atcitty, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Ayrikian, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

BBackman, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Baczkowski, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Baeumer, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56Bahmer, M.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49Baker, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Balciunas, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Bale, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Baltianski, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54Banys, J.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Banys, J.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Barth, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44Baskaran, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Bassim, N.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81Bayer, T. J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10, 16Bayer, T. J.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Bedair, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Beechem, T. E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 76Bell, A. J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Belovickis, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Bencan, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82Benke, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Benoit, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15, 16Berger, S.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66Berweger, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Bhattacharya, A. . . . . . . . . . . . . . . . . . . . . . . . . . . 10Bhattacharyya, R.*. . . . . . . . . . . . . . . . . . . . . . . . . 73Bian, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Billinge, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Birol, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74Birol, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81Bishara, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66Biswas, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63Blair, V. L.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Blanchet, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75Blendell, J.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11, 22Boluki, S.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68Bolvardi, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Boni, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83Bonnough, S. W.* . . . . . . . . . . . . . . . . . . . . . . . . . 32Boona, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Booth, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . 14, 23, 24Bor, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Borman, T. M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Borman, T. M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Boston, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Bowes, P.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Bozin, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Bradesko, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . 34, 82Brahlek, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74Braun, J. L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19, 30Brennan, R. E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54Brennecka, G. L. . . . . . . . . . . . . . . . . . . . . 14, 40, 66Brenner, D.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Brillson, L. J.. . . . . . . . . . . . . . . . . . . . . . . . . . . 55, 80Brodie, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Brova, M. J.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Brova, M. J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Brown, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Brumbach, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Brydson, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Bud’ko, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Budisuharto, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Bullard, T.. . . . . . . . . . . . . . . . . . . . . . . 16, 31, 38, 39Bullard, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32Bulmer, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31, 32Burrows, D. N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Butler, B. D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

CCabral, M. J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64Cai, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Cai, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Cain, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66Campbell, N. . . . . . . . . . . . . . . . . . . . . . . . 28, 55, 80Caneld, P. C.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Cann, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . 37, 40, 58Cao, D. H.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Cao, Y.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Carter, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Carter, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Catalan, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78Chakhalian, J.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Chambers, S.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81Chan, H. M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Chan, M. K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Chan, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Chang, S.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63Chang, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33, 40Chawla, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Chen, F.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72Chen, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77Chen, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Chen, L.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Chen, L.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22, 52Chen, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Chen, W.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Chen, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66, 72Chen, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59Cheng, C. Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16Cheng, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Cheong, S.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Chi, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Cho, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75Cho, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47, 50Cho, S. B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Choi, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82Choi, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64Choi, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Chopdekar, R. V.* . . . . . . . . . . . . . . . . . . . . . . . . . 47Chou, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44Choudhary, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Choudhary, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 79Christianson, A.. . . . . . . . . . . . . . . . . . . . . . . . . . . 71Chu, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44Chu, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83Chyasnavichyus, M. . . . . . . . . . . . . . . . . . . . . . . . 68Ciobanu, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66Clark, M.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49Clarke, D. R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18Cockayne, E.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42Collings, E. W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Colton, Z.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Comes, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75Cooper, V. R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46Cordes, N.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Cordier, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79Cotroneo, V.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Culbertson, C. M. . . . . . . . . . . . . . . . . . . . . . . . . . 57

DDamjanovic, D. . . . . . . . . . . . . . . . . . . . . . 45, 70, 82Daniels, J. . . . . . . . . . . . . . . . . . . . . . . . 45, 70, 71, 82Davila-Rodriguez, J. . . . . . . . . . . . . . . . . . . . . . . . 24Dawes, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Dawley, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23De Souza, R. A. . . . . . . . . . . . . . . . . . . . . . . . . 56, 62De Souza, R. A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Dean, J. S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27, 37DeCost, B.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59Dedon, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15, 60Dehm, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Denis, L. M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57DeRoo, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Detlefs, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70Di Bernardo, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Dickens, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Dickey, E. C.. . . . . . . . . . . . . . . . . . . . . . . . 33, 34, 64Dickey, E. C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Dittmann, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56Dkhil, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Dmowski, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Dolgos, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43, 57Dolgos, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49Domenech, B.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Domingo, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78Dong, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Donovan, B. F.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 18Dougherty, E. R. . . . . . . . . . . . . . . . . . . . . . . . . . . 68Doyle, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72Drazic, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82Drisko, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Drisko, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Du, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72Dudney, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Dürrschnabel, M. . . . . . . . . . . . . . . . . . . . . . . . . . 39Dursun, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51Dursun, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Dwivedi, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Dycus, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Dyer, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36, 46Dynys, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36, 62

Author Index


EEbbing, C. . . . . . . . . . . . . . . . . . . . . . . . . . . 17, 31, 38Edgeton, A. L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80Egami, T.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Egami, T.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Einarsrud, M. . . . . . . . . . . . . . . . . . . . . . . . . . . 33, 34Eisenbach, M.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46El-Faouri, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Elissalde, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Engel-Herbert, R. . . . . . . . . . . . . . . . . . . . . . . . . . 74Eom, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28, 55, 80Esteves, G.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57Etter, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57Evans, J. T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

FFacchetti, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77Falco, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Fan, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77Fan, Q.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Fan, Z.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64Fancher, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Fang, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69Fanton, M. A. . . . . . . . . . . . . . . . . . . . . . . . . . . 33, 40Farghadany, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 62Fast, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43, 49Fast, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59Feighan, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Feldman, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Fennie, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Ferdinandus, M. . . . . . . . . . . . . . . . . . . . . . . . . . . 32Ferri, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Feteira, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Fettkenhauer, C. . . . . . . . . . . . . . . . . . . . . . . . . . . 35Feygenson, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Finkel, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66Finkel, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Finnis, M. W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Floyd, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Foley, B. M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Foley, B.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18, 77Forrester, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Forrester, J. S.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Fox, A.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49Fox, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Fox, G. R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16Freeman, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50Freitag, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Frolov, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52Frömling, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Frömling, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . 39, 73Fry, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54Fu, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Fuentes-Cobas, L. . . . . . . . . . . . . . . . . . . . . . . . . . 12Fujimoto, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67Fulanovic, L.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Funakubo, H. . . . . . . . . . . . . . . . . . . . . . . . 13, 28, 65

GGabor, U. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Gabriel, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59Gabriel, J. J.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Gandy, A. S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Ganesh, P.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68Ganesh, P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79Gao, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51Gao, P.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36Gao, R.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Gao, R.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Garbozi, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24García, R. E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Garrity, K. F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42Gaskins, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Gautum, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31, 38Gemeiner, P.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Genenko, Y. A.. . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Gheorghiu, N.* . . . . . . . . . . . . . . . . . . . . . . . . 17, 38Gibbons, B.. . . . . . . . . . . . . . . . . . . . . . . . . . . . 16, 65Gibbons, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49Giuntini, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Glaum, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Glaum, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Gleich, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Gluhovic, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . 35, 59Goglio, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Goldflam, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76Golt, M. C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67Gonzales, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78Gorzkowski, E.. . . . . . . . . . . . . . . . . . . . . . . . . 20, 46Gorzkowski, E.* . . . . . . . . . . . . . . . . . . . . . . . . 22, 39Graham, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18Grande, T.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Grant, D.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63Gray, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56Greaney, P. A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Green, R. J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55Greene, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81Gresock, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81Gries, U. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56Grimley, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Grimley, E. D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Grimley, E. D.* . . . . . . . . . . . . . . . . . . . . . . . . . 9, 25Grove, K.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16, 49Grutter, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76Gunning, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Guo, E.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Guo, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Guo, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13, 20, 27Guo, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Gupta, S. K.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37Gurdal, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13, 33

HHadad, M.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82Hagerstrom, A. . . . . . . . . . . . . . . . . . . . . . . . . 14, 23Hagerstrom, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . 23Hall, D. A.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Hall, D. A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Hallsteinsen, I.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 76Han, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77Han, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Han, M.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Handley, C.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50Handwerker, C. . . . . . . . . . . . . . . . . . . . . . . . . 11, 22Harding, J. . . . . . . . . . . . . . . . . . . . . . . . . . 27, 37, 50Harrington, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 75Harrington, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Harris, D. T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30Harris, D. T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Harris, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Harrison, N. M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Hartman, S. T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Haskel, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Hattrick-Simpers, J. . . . . . . . . . . . . . . . . . . . . . . . 59Haugan, T. J. . . . . . . . . . . . . . .16, 17, 31, 32, 38, 39Haugan, T. J.*. . . . . . . . . . . . . . . . . . . . . . . 31, 38, 39Haugen, A. B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70He, Q.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63Heath, J. P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 27, 37Hebert, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12, 36Hefferan, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Heinonen, O. . . . . . . . . . . . . . . . . . . . . . . . . . . 36, 46

Heisig, T.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56Henderson, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Hennig, E.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51Hennig, R. G. . . . . . . . . . . . . . . . . . . . . 34, 35, 59, 60Henry, M. D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Herisson de Beauvoir, T. . . . . . . . . . . . . . . . . . . . 27Herisson de Beauvoir, T.* . . . . . . . . . . . . . . . . . . 20Heron, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Herrera, G. M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Hertz, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Hilliker, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37Hinterstein, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Hinterstein, M.*. . . . . . . . . . . . . . . . . . . . . . . . . . . 57Hirose, S.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Hoffman, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69Hoffmann, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Hoffmann, M. J.. . . . . . . . . . . . . . . . . . . . . 11, 27, 57Holmestad, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76Holtz, M.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Hong, S.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63Hong, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Hong, X.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63Hong, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72Hong, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52Hopkins, P. E. . . . . . . . . . . . . . . . .19, 25, 28, 30, 78Hossain, M. D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Hou, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57, 58, 64Huang, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69Huang, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31, 38Huang, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76Huang, W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77Huddleston, W.* . . . . . . . . . . . . . . . . . . . . . . . 36, 62Huey, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70Huey, B.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79Hughes, L. A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54Huijben, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81Hutter, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Hwang, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51Hwang, H.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77Hwang, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

IIhlefeld, J. . . . . . . . . . . . . . . . . . . . . . . . . . . 28, 29, 76In-Tae, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73Irving, D.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Ishikawa, M.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Ito, Y.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Ivanov, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Ivanov, M.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Ivy, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Iyasara, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

JJackson, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Jain, A.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Jain, A.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67Jalan, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80Jalan, B.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74Jana, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Jancar, B.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82Janotti, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80Janotti, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69Jaramillo, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . 56, 69Jeen, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63Jeen, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75Jennings, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Jensen, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81Jeon, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Jeon, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75Jeong, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82Jeong, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

Author Index


Ji, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Ji, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Jia, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Jia, J.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30Jian, G.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74Jiang, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Jiang, X.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Jin, K.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30Jishi, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16Johnson, B. S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Johnson, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37Johnson, S. D.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Jones, J. L. . . . . . . . . . . . . . . . . . . . . . . . . . . 41, 57, 58Jones, J. L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64Jones, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Jorgensen, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Josse, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

KKabos, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Kalkur, T. S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Kan, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75Kang, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50Kang, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Kaplan, W. D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Kareev, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Katiliute, R.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Katiyar, R.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63Kawahara, M.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50Kaxiras, E.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69Keil, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Kelley, K.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Kelley, K.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Kennedy, C. D.*. . . . . . . . . . . . . . . . . . . . . . . . . . . 37Khachaturyan, R.. . . . . . . . . . . . . . . . . . . . . . . . . . 71Khassaf, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12, 46Khatun, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47Khesro, A.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Kiguchi, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13, 28Kim, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67Kim, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50Kim, E.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Kim, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81Kim, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82Kim, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83Kim, S.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51Kim, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50Kim, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37Kingon, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50, 51Kirchlechner, C.. . . . . . . . . . . . . . . . . . . . . . . . . . . 21Kittiwatanakul, S. . . . . . . . . . . . . . . . . . . . . . . . . . 78Kjærnes, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76Kleebe, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10, 39Klein, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Klemm, R. A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32Klemm, R. A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32Knight, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Koch, L.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73Kocic, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20, 39Koh, L.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Kok, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Kolluru, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Konno, T. J. . . . . . . . . . . . . . . . . . . . . . . . . . . . 13, 28Koo, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50, 51Kornecki, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54Koruza, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Kotsonis, G. N.. . . . . . . . . . . . . . . . . . . . . . . . . . . . 30Kotsonis, G. N.*. . . . . . . . . . . . . . . . . . . . . . . . . . . 30Kratofil, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Krayzman, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57Kreisel, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

Kriven, W. M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Krogstad, J. A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Kumar, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78Kumar, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Kuna, L.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46Kuna, L.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36, 46Kupp, E. R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33, 40Kurosawa, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Kursumovic, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . 47Kusne, A.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59Kutnjak, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Kwak, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63Kwong, K.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

LLackner, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35LaFlam, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18Lanagan, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . 16, 19Lange, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Langenberg, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 78Lavery, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Law, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68LeBeau, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . 9, 25, 64LeBeau, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Lee, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Lee, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63, 80Lee, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55, 62, 73Lee, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47, 55, 75Lee, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80Lee, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50, 57Lee, S.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47Lee, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50, 51, 77Lei, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72Lei, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72Leng, C.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Leopoldo, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39LeSar, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66Lester, H.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Levin, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42Levin, I.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57Lewin, G. D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Lewis, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Li, F.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32Li, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Li, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52Li, L.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74, 76Li, L.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18, 79Li, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74Li, Q.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Li, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Li, W.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69Li, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46Li, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Liang, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Lin, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32lind, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Liu, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77Liu, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71, 82Liu, M.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40, 72Liu, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Liu, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Liu, X.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Liu, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Long, C.. . . . . . . . . . . . . . . . . . . . . . . . . . . . 14, 23, 24Long, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Lookman, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Losego, M. D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Losego, M. D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Lou, X.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Lowing, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Lu, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Lu, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Luo, A.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Luo, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9, 32Luo, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52Lupascu, D. C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

MMa, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Ma, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Ma, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80MacManus-Driscoll, J. . . . . . . . . . . . . . . . . . . . . . 47MacManus-Driscoll, J.* . . . . . . . . . . . . . . . . . . . . 41Mahjouri-Samani, M.* . . . . . . . . . . . . . . . . . . . . . 69Maier, R. A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42Maiti, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83Majkut, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Makarovic, M. . . . . . . . . . . . . . . . . . . . . . . 13, 51, 82Maksymovych, P. . . . . . . . . . . . . . . . . . . . . . . . . . 68Malic, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . 34, 70, 82Mangeri, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36, 46Manjón Sanz, A. M.*. . . . . . . . . . . . . . . . . . . . . . . 57Manna, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66Mannodi-Kanakkithodi, A.* . . . . . . . . . . . . . 43, 67Mantri, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Maria, J.. . . . . . . . . . . . . . . . . . .19, 25, 27, 28, 29, 30Marksz, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Marksz, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Marques, F.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36Marquis, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44Martin, L. W. . . . . . . . . . . . . . . . . . . . . . . . . . . 15, 60Martin, L. W.* . . . . . . . . . . . . . . . . . . . . . . . . . 15, 48Martin, S. W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Martinson, A.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Maruyama, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67Mathew, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Mathur, N. D.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Matt, C. E.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69McComb, D. W.*. . . . . . . . . . . . . . . . . . . . . . . . 9, 45McCormack, S. J. . . . . . . . . . . . . . . . . . . . . . . . . . . 53McDowell, M.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . 16McGuire, M.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68McKenzie, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Mecartney, M. . . . . . . . . . . . . . . . . . . . . . . . . . 10, 53Medlin, D.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Meier, Q.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Meier, W. R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Meisenheimer, P. B.* . . . . . . . . . . . . . . . . . . . . . . 25Mertens, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Messing, G. L. . . . . . . . . . . . . . . . . . . . . . . . . . 33, 40Meyer, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73Meyer, R. J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33, 40Michael, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Michie, M. J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Middey, S.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Mikolajick, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Milne, S. J.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Mimura, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Mirrielees, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Mishra, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Misirlioglu, B.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . 83Misture, S. T.* . . . . . . . . . . . . . . . . . . . . . . . . . 22, 56Mitic, V.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20, 39Mitzi, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44Mkhoyan, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80Mondal, S.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78Moore, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69Moradi, O. M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83Moreau, M.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76Morrissey, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Moshe, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Mostaed, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Author Index


Motapothula, M. R.. . . . . . . . . . . . . . . . . . . . . . . . 49Moya, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12MU, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72Muccillo, E. N. . . . . . . . . . . . . . . . . . . . . . . . . . 35, 36Muccillo, E. N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 73Muccillo, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36Mueller, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56Mula, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Mulcahy, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16Muller, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Müller, M. P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56Müller, M. P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62Mundy, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63Murakami, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Muralt, P. R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82Murphy, J.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32Murphy, J. P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Murphy, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72Myers, C.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

NNahm, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51, 77Nahm, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50Nair, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78Nakagawa, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54Nakamura, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Nakhmanson, S.. . . . . . . . . . . . . . . . . . . . . 36, 46, 63Nakhmanson, S.*. . . . . . . . . . . . . . . . . . . . . . . . . . 46Ndayishimiye, A. . . . . . . . . . . . . . . . . . . . . . . . . . . 20Newman, N.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78Noesges, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55, 80Nord, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76Novak, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10, 71

OO’Neill, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Oddershede, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Oganov, A. R.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52Oh, S.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55Olevsky, E. A.* . . . . . . . . . . . . . . . . . . . . . . . . . 43, 53Olsen, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Omar, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73Opila, E. J.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Orloff, N. . . . . . . . . . . . . . . . . . . . . . . . . . . 14, 23, 24Orloff, N.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Ormstrup, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Osofsky, M.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81Otonicar, M.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

PPachuta, K. G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Packard, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66Page, K. L.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Paik, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78Paisley, E. A.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Paisley, E. A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Pal, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Panasyuk, G.. . . . . . . . . . . . . . . . . . . . . . . . . . . 31, 38Panasyuk, G. Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . 39Pandya, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Pareek, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Park, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59Park, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Patel, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36, 46Patel, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12, 36Paterson, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Patterson, B. M.* . . . . . . . . . . . . . . . . . . . . . . . . . . 45Patterson, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Patterson, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Paudel, H. P.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Paudel, T. R. . . . . . . . . . . . . . . . . . . . . . . . . . . . 55, 80

Paul, J. T.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59Paunovic, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . 20, 39Pei, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72Peng, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72Pentzer, E.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Perea, D. E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75Perry, N. H. . . . . . . . . . . . . . . . . . . . . . . . . . . . 60, 75Peters, D.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76Pfeiffenberger, N. . . . . . . . . . . . . . . . . . . . . . . . . . 19Phillpot, S. R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Pintilie, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83Pirie, H.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69Pitike, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46, 63Pitike, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36, 46Polcawich, R. G.. . . . . . . . . . . . . . . . . . . . . . . . 15, 16Popovic, N. B.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Porfirio, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36Potrepka, D. M. . . . . . . . . . . . . . . . . . . . . . . . . 15, 16Poulsen, H. F.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70Pradal Velazquez, E. . . . . . . . . . . . . . . . . . . . . . . . 74Prakash, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80Pramanick, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Pramanick, A.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Prestigiacomo, J. . . . . . . . . . . . . . . . . . . . . . . . . . . 81Prette, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Psychogiou, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Pulskamp, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

QQian, X.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68Qin, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55Quinlan, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Quintero Cortes, F. J. . . . . . . . . . . . . . . . . . . . . . . 16

RRadovic, M.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56Radue, E.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25, 78Raengthon, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Raj, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Rajan, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67, 79Raju, S. V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54Rak, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Ramesh, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70Ramprasad, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67Ran, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Randall, C. . . . . . . . . . 10, 13, 16, 19, 20, 33, 51, 71Randall, C.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Rao, K.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78Rappe, A. M.*. . . . . . . . . . . . . . . . . . . . . . . . . . 44, 52Rath, M.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38Reaney, I. M. . . . . . . . . . . . . . . . . . . . . 26, 37, 40, 48Reaney, I. M.*. . . . . . . . . . . . . . . . . . . . . . . . . . 49, 76Reece, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Reich, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64Reid, P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Reimanis, I.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Reimanis, I.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Reis, S. L.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73Reis, S. L.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Ren, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Ren, Y.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77Revard, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Reyes-Rojas, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Rheinheimer, W. . . . . . . . . . . . . . . . . . . . . . . . . . . 11Rheinheimer, W.* . . . . . . . . . . . . . . . . . . . . . . . . . 11Rickman, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 21, 67Rivas, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18Robinson, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Rödel, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Rodriguez, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16Rohrer, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Rojac, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . 13, 51, 70Rojac, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82Roncal-Herrero, T. . . . . . . . . . . . . . . . . . . . . . . . . 48Rost, C. M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19, 30Rost, C. M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30Rudd, R. E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52Rudy, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Runnerstrom, E. . . . . . . . . . . . . . . . . . . . . . . . 25, 29Rzchowski, M. . . . . . . . . . . . . . . . . . . . . . . 28, 55, 80

SSabino, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69Sabino, F. P.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80Sachet, E.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25, 29Saha, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81Sahu, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Sakamoto, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Sakata, O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Salvo, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Samanta, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Samulionis, V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Sankaranarayanan, V.. . . . . . . . . . . . . . . . . . . . . . 34Sanlialp, M.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Sarangi, V.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Saremi, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Saremi, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Sasaki, K.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75Savva, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Sawatzky, G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55Saxena, M.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83Sayyadishahraki, A.. . . . . . . . . . . . . . . . . . . . . . . . 78Schad, J. L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80Schenk, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Scheu, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Schlom, D. . . . . . . . . . . . . . . . . . . . . . . . . . 23, 28, 78Schmidt, W. L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Schneider, G. A.* . . . . . . . . . . . . . . . . . . . . . . . 21, 54Schneider, J. M. . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Schroeder, U. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Schultheiß, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Schultz, A.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Schwarts, E. D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Schwartz, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Scott, J. F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63Scrymgeour, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Sebastian, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38Sebastian, M.* . . . . . . . . . . . . . . . . . . . . . . . . . 31, 38Sehirlioglu, A. . . . . . . . . . . . . . . . . . . . . . . 36, 61, 62Seifert, D. U.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57Seifert, D. U.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Selbach, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76Selbach, S. M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51Selbach, S. M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Sen, C. M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83Sen, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47, 61Seshadri, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44Sethupathi, K.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Sexton, M.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Shafer, P.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Shaheen, S. E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Shao, H.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74Sharma, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63Sheldon, B. W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Shen, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Shi, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80Shihong, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31, 38Shimizu, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Shimizu, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Shiraishi, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . 13, 28Shoemaker, D. P.* . . . . . . . . . . . . . . . . . . . . . . . . . 57Shomrat, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Author Index


Shrout, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32Simenas, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Simons, H. W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Simons, H. W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 70Sinclair, D. C. . . . . . . . . . . . . . . . . . . . . 26, 27, 37, 48Sinclair, D. C.* . . . . . . . . . . . . . . . . . . . . . . . . . 49, 74Sinclair, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76Skaar Fedje, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Skjærvø, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Slagle, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Smith, C. S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Smith, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78Smith, K. A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Smith, S. W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Smith, S. W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Smolyaninov, I. . . . . . . . . . . . . . . . . . . . . . . . . . . . 81Smolyaninova, V. . . . . . . . . . . . . . . . . . . . . . . . . . 81Sohn, C.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63Soler, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Solis, O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Sortino, E. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Spaldin, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Sparkes, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Spreitzer, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Spurgeon, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75Srolovitz, D. J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Staruch, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Staruch, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66Steffes, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79Steffes, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70Steiner, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39, 73Straszheim, W. E. . . . . . . . . . . . . . . . . . . . . . . . . . 17Studer, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57Su, D.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Su, Q.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76Sumption, M. D. . . . . . . . . . . . . . . . . . . . . . . . 38, 39Sun, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Sun, Z.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Surta, T. W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Susner, M. A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38Susner, M. A.* . . . . . . . . . . . . . . . . . . . . . . . . . 16, 68Suter, R.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Suvorov, D.. . . . . . . . . . . . . . . . . . . . . . . . . . . . 19, 20Svirskas, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

TTakahashi, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81Takamura, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47Takeuchi, I.. . . . . . . . . . . . . . . . . . . . . . . . . . . . 14, 59Takoudis, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63Talapatra, A.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68Talley, K. R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66Tan, X.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64Tang, X.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52Tateyama, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Tautschnig, M. P. . . . . . . . . . . . . . . . . . . . . . . . . . . 9Tchernychova, E.. . . . . . . . . . . . . . . . . . . . . . . . . . 19Tendulkar, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Tenne, D. A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80Thind, A. S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Thomas, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Thompson, P.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66Tian, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Tidrow, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Todd, R. I.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Tong, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72Topsakal, M.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80Tornau, E.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Tran, H. D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67Trapp, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Travis, A. W.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Triamnak, N. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Trinkle, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Trolier-McKinstry, S. . . . . . . . . . . . . . . . . . . . 16, 57Trolier-McKinstry, S. E. . . . . . . . . . . . . . . . . . 51, 65Trolier-McKinstry, S.* . . . . . . . . . . . . . . . . . . . . . 15Tsai, C. F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Tsen, A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68Tseng, K.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Tsuji, K.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16Tsur, Y.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54Tsymbal, E. Y. . . . . . . . . . . . . . . . . . . . . . . . . . 55, 80Tuller, H. L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75Tuncdemir, S.. . . . . . . . . . . . . . . . . . . . . . . . . . 13, 33Tybell, T.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

UUbeh, U. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75Uchida, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Uecker, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Uehashi, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54ullah Jan, S.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Uršič, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19, 82Uršič, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70Usher, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58Usui, T.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Vvan Benthem, K. . . . . . . . . . . . . . . . . . . . . . . . . . . 54van Benthem, K.* . . . . . . . . . . . . . . . . . . . . . . . . . 55Veazey, R. A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Vecchio, K. S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Venkatesan, T. V. . . . . . . . . . . . . . . . . . . . . . . . . . 49Verma, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Viehland, D.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52Vikrant, K. S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Vinci, R. P. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Viola, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Vladimir, S. V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Volkenandt, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Vrabelj, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34, 70

WWachsman, E. D.* . . . . . . . . . . . . . . . . . . . . . . . . . 60Wada, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Walenza-Slabe, J. . . . . . . . . . . . . . . . . . . . . . . . . . . 49Walker, J. . . . . . . . . . . . . . . . . . . . . . . . . . . 13, 57, 71Walker, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51, 65Wallis, T. M.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Wan, D.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49Wang, D.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Wang, G.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Wang, H.. . . . . . . . . . . . . . . . . . . . . . . . 26, 31, 38, 76Wang, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Wang, L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Wang, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Wang, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13, 22Wang, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61, 80Wang, Z.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24, 55Ward, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50Warzoha, R. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18Watson, B. H.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Watson, B. H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Webb, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69Webber, K. G. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39West, A. R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73Weyland, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Wharry, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Whitelock, H.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36Whitelock, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46Williams, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Wilson, A. A.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Wolfenstine, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54Wollmershauser, J. . . . . . . . . . . . . . . . . . . . . . . . . 46Won, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50Won, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51Wong, C.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74Woo, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77Woo, J.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51Woo, S. I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Woodside, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37Wright, B. L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37Wu, J.. . . . . . . . . . . . . . . . . . . . . . . . . . . 31, 33, 38, 40Wu, J.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16, 31Wu, R.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47Wu, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Wu, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49, 74

XXiang, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Xiao, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72Xiao, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Xie, S.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Xie, S.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Xing, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77Xiong, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61XU, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Xu, P.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80Xu, R.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Xu, W. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Xu, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Xue, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Xue, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60Xuetong, Z.. . . . . . . . . . . . . . . . . . . . . . . . . . . . 20, 27

YYadav, A.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Yadav, D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Yamamoto, T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54Yamaura, K.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Yan, B.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49Yan, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71Yan, Q. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Yang, C.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83Yang, F. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49, 74Yang, K.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Ye, Z. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Ye, Z.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32Yen, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83Yerkes, K. L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Yildiz, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75Yoo, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Yoo, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72Yoon, M.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59Yoshida, H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54Yoshida, M. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53Yoshimura, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . 42Yoshio, K. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Yost, B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81Yu, R.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37Yuk, S. F.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46Yun, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

ZZakutayev, A. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66Zapata-Solvas, E. . . . . . . . . . . . . . . . . . . . . . . . . . . 53Zeb, A.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Zhai, J.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50Zhang, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74Zhang, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Zhang, K. H.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82Zhang, L.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10, 74Zhang, L.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48, 59

Author Index


Zhang, S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51, 64Zhang, S.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44, 51Zhang, W.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31, 38Zhang, X. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Zhang, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

Zhang, Y.*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42Zhao, C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64Zhao, J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Zhao, Z.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72Zhou, H. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55, 60

Zhou, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Zhu, Q. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52Zhu, Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48Zhuk, M.* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Documents

The American Ceramic Society 2018 Conference on Electronic ...ceramics.org/.../2018/01/EAM18_Abstracts_WebFinal.pdf · 2 Electronic and Advanced Materials 2018 Introduction This volume