More than a decade ago:Accelerator development enabled visionary science

probe-before-destroy

Haidu et al.

soft x-ray magnetic holography

Wang, et al. PRL (2013)

Today: We need the complementarity of x-rays & electrons to access to the “Ultrafast” & “Ultrasmall”

soft x-ray magnetic holography

probes electrons & spins

probes lattice

nano-UED

FePt

2nm

heat sink

Goal: understand & control materials processes

Wang, et al. PRL (2013) Xiang, et al. SLAC report (2014)

G. Bertero (WD Corp.)

X-rays or electrons? We need both!

R. Henderson, Quarterly Reviews of Biophysics 28 (1995) 171-193.

Electrons:can be manipulated by electric & magnetic fields (microscopy) but have <10nm coherence lengths.

X-rays:Fully coherent beams offer new opportunities for holographic imaging. Soft x-ray resonant inelastic cross sections are comparable to those of electrons, elastic cross sections are much lower.

The Future of Electron Scattering & DiffractionOpportunities for Ultrafast Science

DOE Basic Energy Sciences Needs Workshop Report (2014)

Key Breakthrough Science Opportunities and Challenges

- Atomic Scale Molecular Processes

- Photonic Control of Quantum Materials

- Energy Transport at the Nanoscale

- Mesoscale Materials and Phenomena

- Evolving Interfaces, Nucleation, and Mass Transport

Nano-UED User Facility

UEM User Facility

UltrafastElectron

Microscopy

UltrafastElectron Diffraction

The Future of Electron Scattering & DiffractionHow do we get there?

DOE Basic Energy Sciences Needs Workshop Report (2014)

Controlling processes on the level of electrons:Non-Born-Oppenheimer dynamics in molecules

Ben-N

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• Absorption triggers coupled ultrafast motion of nuclei and electrons, hard to model

• Born-Oppenheimer violation provides fast funnels for steering energy into particular channel

•

M. Centurion LabU. NebraskaAligned CF3I

Guehr, et al.

• requires sub-100 fs with unfocused electron beam at high repetition

rates(UED)

Opportunities for Ultrafast Materials Science

• requires sub-100 fs with focused electron

beam at high repetition rates

(nano-UED)

• nanoscale energy transport

• photonic control of quantum materials

• nanoscale mechanisms of phase transitions

Imaging of Nanoscale Processes

• requires single-shot imaging

(10ps - 10 nm UEM)

• Phase transitions: diffusionless vs. mass transport

• Biological processes

Carbon fixation by bacterial carboxysomes

Nano-UED User Facility

UEM User Facility

UltrafastElectron

Microscopy

UltrafastElectron Diffraction

Early Science Opportunities with UED

Gas phase chemistry (sub-100fs & 100μm beam size): Experimental setup is still under development (requires isolation of gun and sample vacuum).

Materials science will initially be limited by available samples:etching, exfoliation, sample growth of ~ 100μm free standing films needs to be developed)

Development of laser-electron cross correlation schemes:- use laser-induced space charge- electron beam induced dynamics - photo-induced electron-lattice

coupling in wide-bandgap oxides

Early Science Opportunities with UED

Gas phase chemistry (sub-100fs & 100μm beam size): Experimental setup is still under development (requires isolation of gun and sample vacuum).

Materials science will initially be limited by available samples:etching, exfoliation, sample growth of ~ 100μm free standing films needs to be developed)

Development of laser-electron cross correlation schemes:- use laser-induced space charge- electron beam induced dynamics - photo-induced electron-lattice

coupling in wide-bandgap oxidesMeasurement of single-shot electron diffraction from a 40nm FeRh film epitaxially grown on 10 nm MgO IBAD deposited on 100nm SiN.

First results (A. Reid, R. Li, P. Musumeci)