PROGRAMME - LU · 2015-02-05 · 1st International Conference “Photonics Technologies – Riga 2012” 3 Programme for the Training Course 23-25 August, 2012 Thursday, 23 August

1ST INTERNATIONAL CONFERENCE “PHOTONICS TECHNOLOGIES – RIGA 2012”

August 27-28, 2012

EXHIBITION FOR “HIGH-TECH” SMES “PHOTONICS TECHNOLOGIES – BALTICS 2012”

August 27, 2012

RESEARCH TRAINING COURSE “PHOTONICS TECHNOLOGIES – RIGA 2012”

August 23-25, 2012

PROGRAMME ABSTRACTS

Supported by:

FP7 project FOTONIKA-LV

Grant agreement No 285912

1st International Conference “Photonics Technologies – Riga 2012”2

Supported by FP7 projectUnlocking and Boosting Research Potential for Photonics in Latvia – Towards Effective Integration in the European Research Area (FOTONIKA-LV)FP7-REGPOT-CT-2011-285912

Complementary event:Brokerage on Photonics for FP7 ICT-2013 Calls 10 and 11,

August 27, 2012 (9.00-14.00)

Hotel “Radi un Draugi”, Mārstaļu str. 3

Conference organisers

Conference Scientific BoardDr. Hab Uldis Berzinsh, Latvia – ChairDr. Janis Alnis, DE & LVDr. Andris Azens, LatviaDr. Sergey Babichenko, EstoniaProf. Klaas Bergmann, GermanyProf. Dainis Dravins, SwedenDr. Aigars Ekers, LatviaProf. Ricardas Rotomskis, LithuaniaProf. Janis Spigulis, LatviaProf. Sune Svanberg, SwedenDr. Arnolds Ubelis, LatviaDr. Roman Viter, Ukraine

Conference Local Organising CommitteeMSc. Dina Bērziņa – ChairDr. Arnolds UbelisMSc. Natalija Lesina Prof. Janis SpigulisDr. Janis BalodisDr. Ilgmars EglitisDr. Janis Klavins

© University of Latvia

ISBN 978-9984-45-562-4

1st International Conference “Photonics Technologies – Riga 2012” 3

Programme for the Training Course 23-25 August, 2012

Thursday, 23 August 9.00-18.30 BIOPHOTONICSStefan Andersson-Engels, SE Optical spectroscopy for biomedical diagnostics and

therapy guidanceMatti Kinnunen, FI Light-matter interaction studies in red blood cell

suspensions and at a single cell levelAlexander V. Priezzhev, RU Optical techniques to study blood microrheologic

properties and microcirculationKatarina Svanberg, SE Photonics – can it solve some challenges for patients in

oncology and pediatrics?Sune Svanberg, SE Optical spectroscopy in environmental and medical

research

Friday, 24 August 9.00-16.00 PHOTONICS TECHNOLOGIES

Anssi Mäkynen, FI Optical industrial inspection

David Pegg, USA The Story of the Oak Ridge National Laboratory

Dag Hanstorp, SE Mass and laser spectroscopy of negative ions

Dag Hanstorp, SE Micro fluidics and Optical manipulation

Saturday, 25 August 9.00-15.00 SPACE TECHNOLOGIESJanis Alnis, DE-LV Precision measurements with optical frequency combsHenrik Cederquist, SE Interactions with carbon bearing molecules and cluster –

fullerenes and Polycyclic Aromatic HydrocarbonsSLR technologies including working visit to the Geodynamics Observatory

(in LU Botanic Garden) of Institute of Astronomy University of Latvia


Agenda for the Conference 27-28 August, 2012

Monday, 27 August, 201212.00-17.00 Exhibition for “high-tech” SMEs

“Photonics Technologies – Baltics 2012”14.30 Welcome and opening remarks:

On behalf of Local and International Scientific Boards Mrs. Dina Bērziņa, Dr. Hab. Uldis Berzinsh;

On behalf of the Saeima of the Republic of Latvia, MP Dr. Atis Lejins;On behalf of FP7-REGPOT-2011-1 project FOTONIKA-LV: Chair of Steering

Committee Prof. Andrejs Silins;Dr. Arnolds Ubelis. Coordinator of the Project: Unlocking and Boosting

Research Potential for Photonics in Latvia – Towards Effective Integration in the European Research Area, FP7-REGPOT-2011-1, Nr. 285912 / FOTONIKA-LV, www.lu.lv/fotonika-lv

14.50 First plenary: Future Photonics TechnologiesDr. Janis Alnis, LV. Presentation of ERC Advanced Grant Multidimensional

laser frequency comb spectroscopy of molecules (MULTICOMB). Project leader: Prof. Dr. Theodor W. Hänsch

Invited Speaker on developments in Technology Platform Photonics 21 or Invited Speaker on advances of UK Photonics Strategy

Prof. Andris Ambainis, LV. Theory of quantum computing

13.00-17.30Standby part

of poster session

16.20-17.30

Poster Sessions for students/ young researchers on conference topics• A: Photonics in air and space – Moderated by Kalvis Salminsh• B: Biophotonics – Moderated by Prof. Janis Spigulis• C: Photonics in the micro-world and in nanotechnologies –

Moderated by Dr. Janis Klavins• D: Photonics for Environment protection and monitoring –

Moderated by Dr. Arnolds Ubelis

Tuesday, 28 August, 20129.00 Second plenary:

Advances in Photonics Technologies from Space to the Nano-worldDr. Saleh Ahmed, UK. Space in the UKProf. Klaas Bergmann, DE. A new concept for high accuracy and/or high speed

laser rangingProf. David Pegg, USA. Fast Ion Beam SpectroscopyProf. Henrik Cederquist, SE. The DESIREE-facility – a new instrument for studies

of ion interactionsProf. Dag Hanstorp, SE & H. Hultgren, M. Eklund, I. Yu. Kiyan, DE. Visualization

of electronic motion in an atomic ground stateDr. I. Eglitis, LV & Dr. K. Cernis, LT. Observations of asteroids with Schmidt

telescope in BaldoneS. Babichenko, A. Lisin, L. Poryvkina, S. Shchemelyov, I. Sobolev, EE.

Environmental monitoring with hyperspectral lidarsTanya Nikolova, EC. tbc. DG CNECT, Photonics Unit

14.45 Parallel Sessions• A: Air & space • C: Micro and Nano-worlds• B: Biophotonics • D: Photonics entrepreneurship


A)Chaired by: Dr.Ilgmars Eglitis

1. K. Lapuska, K. Salmins, LV. Geodynamic laboratory at the Institute of Astronomy

2. A. Barzdis, LV. High resolution stellar spectroscopy3. E. Kaziņa, I. Eglitis, LV. The quest of weak carbon stars in the Milky Way

Galaxy4. M. Abele, K. Lapuska, LV & J. Alnis, DE-LV. Advances in Laser ranging tech-

nologies in distance measurements in Space5. J. C. G. Martinez, ES & U. Gross, J. Blahins, A. Apsitis, A. Ubelis, LV. Advance-

ment of ROFLEX instrument6. A. Zariņš, M. Ābele, J. Balodis, I. Janpaule, M. Normand, A. Rubans, LV. Ap-

plication of photonics at the Institute of Geodesy and Geoinformation7. A. Ubelis, M. Abele, LV. FP7-PEOPLE-2011-IRSES-2011 project Nr. 294949 –

NOCTURNAL ATMOSPHERE “Secondary photochemical reactions and tech-nologies for active remote sensing of nocturnal atmosphere”

B)Chaired by: Dr. Jānis Alnis

1. J. Spigulis, LV. FP7 – ERA-NET+ 2012 BIOPHOTONICS2. R. Rotomskis, LT. Biophotonics in cancer therapy: nanotechnological aspects3. A. V. Priezzhev, RU. Optical study of the effect of nanoparticles on micror-

heologic properties of blood and the problem of nanosafety4. V. Karabanovas, LT. Accumulation and intracellular distribution of non-tar-

geted quantum dots – FLIM and confocal imaging 5. R. Kubiliūtė, A. Šlėktaitė, M. Matulionytė, N. Dzingelevičius, R. Rotomskis, LT.

Fluorescent gold nanoparticles stabilized by polyethylene glycol for biomedi-cal application

6. J. Valanciunaite, A. Skripka, G. Spogis, S. Steponkiene, R. Rotomskis, LT. Photo sensitized tumour therapy based on the complex quantum dot-pho-tosensitizer

7. R. Viter, UA & A. Ubelis, LV. FP7-IRSES-2012 project “Development of na-notechnology based biosensors for agriculture” Nr. 318520 – BIOSENSORS-AGRICULT

C)-D)Chaired by: Dr. Janis Klavinsand/orArnolds Ubelis

1. J. Blahins, A. Apsitis, LV & D. Hanstorp, SE. Mobile ion beam instrument2. V. Khranovskyy, SE. Crystal phases engineering effect on the light emission

spectra of ZnO3. A. Ekers, K. Miculis, T. Kirova, M. Bruvelis, A. Cinins, L. Kalvans, M. Auzinsh,

LV & N. Bezuglov, LV-RU & C. Andreeva, LV-BG & D. Efimov, RU. Applications of laser manipulation of adiabatic states

4. S. Babichenko, EE. Baltics Photonics Cluster5. U. Berzinsh, LV. The Development of Laser Pattern Generators from Single

Beam in Rectangular Coordinates to Stamps in Polar Coordinates6. A. Lusis, G. Bajars, I. Liepiņa, LV. Nanotechnologies for developing photo-

catalytic materials7. E. Gavars, M. Stafeckis, D. Pfafrods, LV. Fiber optics components of Z-Light8. J. Blahins, LV, M. Svilans, LV&CA. Vacuum Sputtering technologies9. Dr. Anna Bulycheva, Dr. Mihail Shorohovs, Dr. Vladimir Gostilo, LV. Multide-

tector arrays based on wide band gap crystals for X- and Gamma rays regis-tration

17.00 Round Table Discussion –Future challenges of research in photonics in the Baltics and opportunities offered by FP7 and coming HORIZON 2020

18.30 Closing

Monday, 27 August, 20129.00-14.00 Complementary event

Brokerage on Photonics for FP7 ICT-2013 Calls 10 and 11


ContentsJ. AlnisPresentation of ERC Advanced Grant Multidimensional Laser Frequency Comb Spectroscopy of Molecules (MULTICOMB) . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 8D. PeggThe Evolution of Accelerator-Based Ion Spectroscopy .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 9H. CederquistDESIREE – a New Facility for Studies with Simple and Complex Ions at Stockholm University . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 10D. Hanstorp, H. Hultgren, M. Eklund, I. Y. KiyanVisualization of Electronic Motion in an Atomic Ground State .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 11I. Eglitis, K. ČernisObservations of Asteroids with Schmidt Telescope in Baldone . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 12A. BarzdisHigh-Resolution Stellar Spectroscopy .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 13E. Kazina, I. EglitisThe Quest of Weak Carbon Stars in the Milky Way Galaxy .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 14J. C. G. Martinez, U. Gross, J. Blahins, A. Apsitis, A. UbelisAdvancement of ROFLEX Instrument .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 15M. Ābele, J. Balodis, I. Jaunpaule, M. Normand, A. Rubāns, A. ZariņšApplication of Photonics at the Institute of Geodesy and Geoinformation .. .. .. .. .. .. .. .. .. 16A. Ubelis, M. Abele, J. VjatersFP7-PEOPLE -2011- IRSES-2011 Project Nr. 294949 – NOCTURNAL ATMOSPHERE “Secondary Photochemical Reactions and Technologies for Active Remote Sensing of Nocturnal Atmosphere” .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 17R. RotomskisBiophotonics in Cancer Therapy: Nanotechnological Aspects .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 18R. Viter, A. Ubelis,FP7-IRSES-2012 Project “Development of Nanotechnology Based Biosensors for Agriculture” Nr.318520 – BIOSENSORS-AGRICULT . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 19J. Blahins, A. Apsitis, J. Klavins, U. Berzinsh, D. HanstorpGRIBAM; Gotheburg-Riga-Ion-Beam-Apparatus (Mobile), Design and First Results . .. .. .. .. 21I. Kaulachs, G. Shlihta, P. Shipkovs , A. Ivanova, M. Roze, A. CielavsSolution-Processed Organic Bulk Heterojunction Bi-Layer Photovoltaic Cell with Non-Planar Phthalocyanine . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 22A. Ekers, N. Bezuglov, K. Miculis T. Kirova, M. Bruvelis, D. Efimov, C. Andreeva, A. Cinins, L. Kalvans, M. AuzinshApplications of Laser Manipulation of Adiabatic States . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 23U. BerzinshThe Development of Laser Pattern Generators from Single Beam in Rectangular Coordinates to Stamps in Polar Coordinates .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 24A. Bulycheva, M. Shorohov, V. GostiloMultidetector Arrays Based on Wide Band Gap Crystals for X- and Gamma Rays Registration . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 25S. Ahlberg, F. Rancan, A. Vogt, J. Lademann, C. Graf, D. Neumann, C. Greulich, J. Diendorf , M. C. MeinkePenetration and Toxicity of Nanoparticles in a Human Keratinocytes Cell Line and Human Skin Explants.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 26Z. Alute, R. Viter, A. A. Chaaya, M. Bechelany, D. ErtsStructural and Optical Properties of ZnO Nanostructures Deposited by Atomic Layer Deposition .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 27


M. E. DarvinResonance Raman Spectroscopy as a Non-Invasive Optical Method for Non-Direct Screening the Generation of Reactive Oxygen Species in Human Skin . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 28K. DomkinMultifuses Bbased on Polymer-Carbon Nanocomposites . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 29M. O. Eriksson, Chih-Wei Hsu, E. S. Moskalenko, A. Lundskog, S. Amloy, K. F. Karlsson, P. Bergman, E. Janzén, P. O. HoltzDynamics of Excitonic Complexes in Single InGaN Quantum Dots .. .. .. .. .. .. .. .. .. .. .. .. .. .. 30O. Isaksson, V. M. Ando, M. Karlsteen, D. HanstorpLevitation and Manipulation of Aerosol Particles by Radiation Pressure . .. .. .. .. .. .. .. .. .. .. 31D. Jakovels, I. Kuzmina, A. Berzina, J. SpigulisSkin Hemoglobin Assessment by Spectral Imaging . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 32I. Janpaule, D. Haritonova, K. MorozovaPhotonics Results Applied in GNSS and Geoid Determination .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 33Y. Kee, D. Cremers, J. KimGroupwise Shape Registration Based on Entropy Minimization .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 34V. Khranovskyy, L. Hultman, R. YakimovaBasal Plane Stacking Faults Related luminescence in ZnO Nanostructures . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 35M. Kukk, M. Kriisa, E. Kärber, M. KrunksThe Effect of Solution Spraying Rate on the Properties of Chemically Sprayed ZnO:In Thin Films .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 36A. LaurePhotonics Technologies in Astrospectroscopy . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 37I. Pylypenko, N. StarodubOptical Approach for the Express Registration of Total Toxicity of Environmental Objects . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 38J. RohlénResonances and Threshold in Negative Ion Photodetachment . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 39K. Shavanova, N. StarodubExperimental Examination of Efficiency of Express Control of Horse Chestnut Tree State by Portable Optical Instrument .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 40A. Skripka, J. Valančiūnaitė, R. RotomskisComplex of Chlorin e6 and Quantum Dots Coated by Different Phospholipids: Stability and Spectral Properties .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 41A. Šlėktaitė, R. Kubiliūtė, R. RotomskisFluorescent Gold Nanoclusters for X-Ray Imaging . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 42S. N. Flyshyk, N. F. StarodubStructured Nano-Porous Silicon as Transducer of Immume Biosensor at the Control of Mycotoxins . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 43I. SobolevReferencing Satellite Data with LIF and SFS Technique in the Multi-Tier Monitoring Model .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 44R. Son’ko, N. StarodubEffect of Induction of Chlorophyll Fluorescence as Express Approach for Diagnostics of General State of Plants.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 45K. Stašys, V. Karabanovas, R. RotomskisQuantum Dots as Drug Delivery System for Phallotoxin .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 46Alla Tereschenko, Roman Viter, Nikolay Starodub, Yulia Ogorodniichuk, Valentyn SmyntynaPhotoluminescence Immune Biosensor for Salmonella Detection, Based on TiO2 Nanowires.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 48


Presentation of ERC Advanced Grant Multidimensional Laser Frequency Comb Spectroscopy of Molecules (MULTICOMB)

J. AlnisMax Planck Institute of Quantum Optics

Hans Kopfermann Str. 1, 85748 Garching, Germany

EU advanced researcher grant “Multicomb” has a goal to expand femtosecond optical frequency combs to infrared region where most gasses have strong absorption signatures. It is hosted in the research group of Prof. Theodor Hänsch and principal investigator is Dr. Nathalie Picqué.

Traditional technique for gas spectroscopic analysis in the infrared region is using Fourier transform spectrometers. Fourier transform spectrometers are based on Michelson interferometer with one moving mirror.

“Multicomb” method is based on interference of two slightly-detuned femtosecond frequency combs. One comb beam is sent through the gas sample and other comb beam is used as a reference. Fast photodiode detector records a beat note between two beams and converts information into radio frequency (RF) domain. RF beatnote signal appears when both comb pulses overlap simultaneously on the photodetector. As one comb has passed gas sample some spectral regions have been attenuated and beatnote pulse shape changes. Fourier transformation converts RF pulse signal from time domain into frequency domain revealing gas absorption spectrum.

Dual comb spectroscopy method has an advantage over traditional Fourier transform spectrometer as it does not require any moving parts. Without any moving parts it is possible to acquire spectrally broad spectra quickly (10 ms) that is important for studying fast chemical processes.

References [1] B. Bernhardt, A. Ozawa, P. Jacquet, M. Jacquey, Y., T. Udem, R. Holzwarth, G. Guelachvili, T. W.

Hänsch and N. Picqué, Cavity-enhanced dual comb spectroscopy Nature Photonics 4, 55 (2010)[2] B. Bernhardt, E. Sorokin, P. Jacquet, R. Thon, T. Becker, I. T. Sorokina, N. Picqué and T. W. Hänsch,

Applied Physics B - Lasers and Optics 100, 3 (2010).

Abstracts 9

The Evolution of Accelerator-Based Ion Spectroscopy

D. PeggUniversity of Tennessee, USA

Ion Spectroscopy: Developments in accelerator-based spectroscopy of positive ions will be discussed. Examples of Beam-Foil Spectroscopy(BFS) will be shown. It was the precursor of the present method of Fast Ion Beam Laser Spectroscopy (FIBLAS). The use of FIBLAS in frequency-resolved and time-resolved will be addressed.


DESIREE – a New Facility for Studies with Simple and Complex Ions at Stockholm University

H. Cederquist

The acronym DESIREE stands for Double ElectroStatic Ion Ring ExpEriment. The DESIREE facility has two main instruments. One of them consists of two cryogenically operated 8,8- meters circumference electrostatic ion storage rings with a common section for merged ion beams experiments. The other one is a stand-alone beam line, equipped with a cryogenic radio-frequency ring electrode trap, for single pass experiments where internally cooled ions interact with gas targets and/or lasers. The two storage rings are served by ion sources from separate injector platforms and are contained in an inner vacuum chamber which will be cooled to about 10 K. Given time the stored ions will assume the same internal temperature as the walls of the chamber, i.e. 10 K, where long storage times may be achieved given the low background pressure, which is expected to be in the 10-14 mbar range in cold operation. The inner vacuum chamber will be cooled by four cryogenerators and is thermally isolated by a heat screen at held 50 K and an outer steel vacuum chamber at room temperature. The experimental program will include studies of the inherent stabilities of ions, interactions between pairs of ions down to the meV collision energy range, action spectroscopy with internally cold ions, interactions with clusters etc.

Abstracts 11

Visualization of Electronic Motion in an Atomic Ground State

D. Hanstorp1, H. Hultgren2, M. Eklund2, I. Y. Kiyan2

1 University of Gothenburg, SE- 412 96 Gothenburg, Sweden 2 Institute of Physics, University of Freiburg, 79104 Freiburg, Germany

The advance of femto- and attosecond lasers has opened up for time resolved studies of electronic dynamics in atoms and molecules. In this talk a novel method for direct visualization of electronic motion in the ground state of atoms will be presented. Femtosecond pump-probe laser spectroscopy, combined with velocity map imaging, is used to project the electron density distribution of an atom onto a detector. The pump laser pulse creates a coherent electronic wave packet in the ground state of the atom through multiphoton detachment of its parent negative ion. This wave packet is subsequently probed by strong field ionization by a second laser pulse. A strong temporal modulation in the yield of ionized electrons, due to a periodic spatial rearrangement of the electron cloud in the atom, is observed. The method has been applied to carbon and silicon atoms.


Observations of Asteroids with Schmidt Telescope in Baldone

I. Eglitis1, K. Černis2

1 Institute of Astronomy, University of Latvia, 19 Raina blvd., Riga, Latvia, LV-1586

2 Institute of Theoretical Physics and Astronomy, Vilnius University, Goštauto St. 12, Vilnius, Lithuania, LT-01108

A brief overview of the main types and bands of asteroids is given. The performance of Baldone Observatory since 2008 in exploration of Solar system small body is revealed. A problem on the asteroid hazard degree to Earth civilization is discussed. Given the asteroids fall timeline. Some aspects of the nearest future of asteroid research are looked.

Abstracts 13

High-Resolution Stellar Spectroscopy

A. BarzdisInstitute of Astronomy, University of Latvia, 19 Raina blvd.,

Riga, Latvia, LV-1586

Spectroscopy is an important tool that allows to investigate the chemical composition of astronomical objects. During recent years high-resolution stellar spectroscopy has gained high attention to astronomers, since it allows to obtain accurate abundances of stars at different evolutionary stages. One of the most rapidly evolving directions of research are high-resolution spectroscopy of metal-poor stars of the Galaxy and its nearby satellites. These investigations provide significant information about the evolution of the Galaxy and nucleosynthesis in the early Universe. For example, detection of spectral lines of short-lived isotopes, such as 238U and 232Th in the spectra od metal-poor stars has allowed to determine the ages of individual stars. Although high-resolution spectroscopy of metal-poor and Solar-type stars is quite simple, spectroscopy of late type stars, such as carbon stars can still be difficult and requires different approach, appropriate model atmospheres, and high quality molecular line lists. The current methods and problems of high-resolution stellar spectroscopy are discussed.


The Quest of Weak Carbon Stars in the Milky Way Galaxy

E. Kazina, I. EglitisInstitute of Astronomy, University of Latvia,

19 Raina blvd., Riga, Latvia, LV-1586

Fundamental parameters (Teff, distance r, absolute magnitude Mk, bolometric magnitude Mbol) of 8 studied CGCS stars and 8 newly discovered carbon stars in the Baldone Astrophysical observatory are presented. The correlation of gradient [7570-6750] with effective temperature is confirmed on the basis of 191 late C-star sample. Fundamental parameters obtained with the analysis of the C-stars low resolution spectra are in agreement with theoretical calculations. Since carbon stars belong to an older population, than young star clusters and associations, they are more weakly tied to spiral arms, as show our distances.It should be noted that calculations of models are needed for lower temperatures and this kind of analysis requires simultaneous spectral, and IR observation in J, K passbands to reduce the impact of star brightness variation on the results.

Abstracts 15

Advancement of ROFLEX Instrument

J. C. G. Martinez1, U. Gross2, J. Blahins2, A. Apsitis2, A. Ubelis2

1 Laboratory for Atmospheric and Climate Science (CIAC), CSIC, Toledo, Spain 2 Association FOTONIKA-LV, University of Latvia

The ROFLEX is a new instrument for in situ detection of atmospheric iodine atoms and molecules based on atomic and molecular resonance and off-resonance ultravio-let fluorescence excited by lamp emission1. The instrument combines the robustness, light weight, low power consumption and efficient excitation of radio-frequency pow-ered electrodeless light sources with the high sensitivity of the photon counting tech-nique. Calibration of fluorescence is achieved via quantitative detection of the molecule by incoherent broad band cavity-enhanced absorption spectroscopy. Atomic iodine fluorescence signal is calibrated by controlled broad band photolysis of known concen-trations in the visible spectral range at atmospheric pressure. The instrument has been optimised inlaboratory experiments to reach detection limits of 1.2 pptv for I atoms and 20 pptv for for S/N=1 and 10 min of integration time. The ROFLEX system has been deployed in a field campaign in Northern Spain, representing the first concurrent obser-vation of ambient mixing ratios of iodine atoms and molecules in the 1–350 pptv range.In mentioned article has been showed that studies of atmospheric iodine chemistry have been mainly motivated by its impact on the oxidizing capacity of the MBL by cata-lyzing O3 destruction. Another focus of interest is the involvement of iodine oxides in the formation of ultra-fine particles in the coastal MBL, which may grow to a size where they can act as cloud condensation nuclei. Iodine is released to the atmosphere mainly in the form of I2 and alkyl iodides such as CH3I and CH2I2 by coastal and oceanic biological sources. In the troposphere, I atoms are released by photolysis of I2 and iodocar bons.Further optimisation of the instrument goes towards reducing the detection limit for I2 by an order of magnitude and increasing the lifetime of the lamps. RF power source also has been further developed. Besides that, the challenge is to adapt the ROFLEX instrument for bromine measure-ments. Bromine concentration in atmosphere has natural and man made origins and it’s vital for the research on atmosphere composition sustainability2 to have mobile field instrument ensuring high accuracy measurements. Author in3 says “among other effects, bromine released by biological processes in the oceans apparently reduces ozone levels in the troposphere. This source may be a link between atmospheric composition and climate change”. …”low levels of ozone in the atmosphere’s lowermost layer, the tropo-sphere, during the polar spring result from bromine released from melting sea ice and ‘frost flowers”.Therefore RF powered electrodeless bromine atomic spectra source for ROFLEX should be developed. Positioning of bromine atomic resonance spectra lines in VUV region means and demands a lot of sophisticated technological solutions to be found for the success.

1 In situ detection of atomic and molecular iodine using resonance and off-resonance fluorescence by lamp excitation: ROFLEX J. C. Gómez Martín, J. Blahins, U. Gross, T. Ingham, A. Goddard, A. S. Mahajan, A. Ubelis, and A. Saiz-Lopez. Atmospheric Measurement Techniques, 2010 AMTD - Atmos. Meas. Tech., 4, 29-45, 2011

2 Field and satellite observations of the formation and distribution of Arctic atmospheric bromine above a rejuvenated sea ice cover. JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 117, D00S05, 15 PP., 2012.

3 Ross J. Salawitch. Atmospheric chemistry: Biogenic bromine. Nature 439, 275-277 (19 January 2006), onine 18 January 2006


Application of Photonics at the Institute of Geodesy and Geoinformation

M. Ābele, J. Balodis, I. Jaunpaule, M. Normand, A. Rubāns, A. ZariņšAssociation FOTONIKA-LV, University of Latvia

Research profile of GGI includes several areas, depending on photonics as instrument of research. The main of them are:

• SLR telescope design. SLR telescopes and their control and data processing software have been promoted by the GGI research team since their very beginning in 1970-s, initially within the Astronomical observatory of the University of Latvia. Presently our particular target is to design a mobile, cheap and robust SLR unit, capable of low and middle-range (up to Lageos type satellites) ranging, including daylight and unguided observations.

• Digital zenith camera project was started in 2010. Recent advances in a number of scientific and technological fields have made possible direct measurement of vertical deflections using astrometric methods. Such measurements are becoming increasingly important along with availability of accurate geocentric positions from GNSS systems, as detailed local geoid properties are needed to put GNSS data to efficient use. Zenith cameras for this kind of measurements have been designed and are being designed by some research groups, yet their number and accessibility is still small. The goal of GGI is to make a portable, cheap and robust instrument, using standard components as much, as possible and ensuring necessary properties by sophisticated data processing algorithms.

Abstracts 17

FP7-PEOPLE -2011- IRSES-2011 Project Nr. 294949 – NOCTURNAL ATMOSPHERE “Secondary Photochemical

Reactions and Technologies for Active Remote Sensing of Nocturnal Atmosphere”

A. Ubelis, M. Abele, J. VjatersAssociation FOTONIKA-LV, University of Latvia

It is becoming more and more evident that global changes in atmospheric composition directly affect many aspects of life on the Earth, determining climate, air quality, and atmospheric inputs to ecosystems. In turn, these changes affect the fundamental needs for human existence and sustainable development on Earth: human health, food pro-duction, health of ecosystems, and the entire biosphere1. In particular, the destruction of the ozone layer can be assumed to be the first signal that risk management strategies should be applied to atmospheric safety and sustainability2, 3, 4.Regarding the short history of the Earths atmospheric research, it is logical to conclude that existing research and monitoring efforts are only beginning steps and the search for novel approaches and research methodologies of theoretical, laboratory and field research, including remote sensing technologies and satellite application, are needed more than ever. In particular, the problems of nocturnal atmosphere and specifically secondary photochemical reactions need significantly more attention.The key objective of the “NOCTURNAL ATMOSPHERE” project is to carry out coordi-nated transfer of knowledge measures between participating teams in the EU (Riga, Bremen, Mainz), in the Ukraine (Kyiv) and Russia (Moscow) with the aim of restoring and strengthening scientific partnership and of developing new collaboration for long lasting synergy, to enhance the level of scientific excellence of participating early stage and experienced researchers. The transfer of knowledge and achievement of intellec-tual “critical mass” will occur through performing theoretical exercises and laboratory research in the important and growing field of secondary photochemical reactions in the Earth’s nocturnal atmosphere and in development breakthroughs of active remote sensing technologies for night-time cartography of the troposphere and stratosphere.The challenge is to create a unique instrument for ranging sensors on satellite, crossing night-time sky segment , with a combined laser&white light beam from the Earth. The consortia members have relevant theoretical and experimental research experience and specific technical skills to achieve progress in research on the nocturnal atmosphere.The aim is to amplify their knowledge and skills via research work on specific work packages and a transfer of knowledge component consisting of seminars, workshops and a summer school which will ensure the effective dissemination of results and fos-ter interactions amongst the young researchers and PhD students.They will be men-tored by and intensively exposed to a culture of international collaborative research.

1 W. Steffen, A. Sanderson, P.D. Tyson, et al. (2004) Global Change and the Earth system: Planet Under Pressure. The IGBP Book Series, Springer-Verlag, Berlin, Heidelberg, New York, 336 p.

2 F. Sherwood Rowland (1995) Stratospheric Ozone Depletion by Chlorofluorocarbons (Nobel Lecture). In: Encyclopedia of Earth, Eds. C.J. Cleveland (2009). Available at http://www.eoearth.org/.

3 http://en.wikipedia.org/wiki/Ozone_depletion. in Wikipedia.4 Michael Carlowicz , May 13, 2009. The World We Avoided by Protecting the Ozone Layer. http://

earthobservatory.nasa.gov/Features/WorldWithoutOzone/printall.php


Biophotonics in Cancer Therapy: Nanotechnological Aspects

R. RotomskisBiomedical physics laboratory of Institute of Oncology, and Laser Research Center,

Vilnius University

Cancer is a leading cause of death worldwide. Late diagnosis and inefficient treatment lead to large number of deaths every year. Therefore many new technologies are offered to bring new solutions for fighting this disease. One of them is photodynamic therapy (PDT), a minimally invasive therapeutic modality presently approved for treatment of several types of cancer and non-oncological disorders. Though PDT is a selective modality, it can be further enhanced by combining other targeted therapeutic strategies that include the use of nanoparticles for selective delivery of photosensitizers. Nanotechnology can offer new solutions for fighting cancer. Due to nano-dimensions, unique optical properties, high stability and easy surface modification by binding different functional groups and biomolecules, semiconductor quantum dots (QDs) and other nanoparticles are considered as promising materials for many medical applications.Naturally occurring differences in the optical properties of normal and cancerous tissue have been exploited frequently in optical detection systems. However, optical biopsy of cancer can be improved by using targeted, optically active and bright contrast agents to enhance the optical signal from disease-specific molecular markers. Nanotechnology has advanced greatly in recent years and can be applied to optical biopsy of cancer in clinical settings. Optically efficient, cancer specific nanoparticles provide a new tool to enable non-invasive visualization of disease-specific molecular and tissue changes with subcellular spatial resolution. Nanotechnology is in a unique position to transform cancer diagnostics and therapy and to produce a new generation of fluorescent nanomarkers and nanodrugs with higher sensitivity and precision of recognition and therapeutic potential.

Abstracts 19

FP7-IRSES-2012 Project “Development of Nanotechnology Based Biosensors for Agriculture” Nr.318520 – BIOSENSORS-AGRICULT

R. Viter, A. Ubelis,Association FOTONIKA-LV, University of Latvia

Metal oxides are well known materials for sensor technologies1. During last decade the attention has been paid to metal oxide nanostructures2. Nanosystems have the smallest dimension structures that can be used for efficient transport of electrons and are thus critical to the function and integration of these nanoscale devices. Because of their high surface-to-volume ratio and tunable electron transport properties through quantum confinement effect, their electrical, optical and sensitive properties are strongly sensitive to minor perturbations3.Metal oxides are good candidates for templates in biosensitive layers. They show good affinity to biological molecules. Among a number of metal oxides, TiO2, Al2O2, ZnO, SnO2 and SiO2 are widely used for sensor and biosensor application. This peculiarity was widely used in amperometric biosensors to detect glucose4. However, other optical properties such as absorption and photoluminescence are not sufficiently often used in biosensor devices. Besides, optical fibers and on-chip technology are widely used in life science applications. Traditionally, biosensors are applied in the domain of medicine5 and in various other domains like environment, defence bioprocessing, food technology etc.6. Agriculture has needs and applications for biosensors detection7 . It is important to control soil content, to control food quality and to prevent animal and plant diseases.The objective of the “Development of Nanotechnology Based Biosensors for Agriculture” project is the coordinated transfer of knowledge and training activities between participating teams in the EU (Riga, Linkoping, Montpellier), in the Ukraine (Odessa and Kyiv) and the Belarus (Minsk) to ensure longlastig collaboration and to enhance the scientific excellence of participating early stage and experienced researchers. The transfer of knowledge will occur through theoretical exercises and laboratory research in the important and growing field of optical fibre biosensors, aiming towards applications in agriculture and taking opportunities offered by the latest achievements

1 V. E. Bochenkov, G. B. Sergeev, Sensitivity, Selectivity and Stability of Gas-Sensitive Metal Oxide Nanostructures, Volume 3: Pages 31-52, Metal Oxide Nanostructures and Their Applications, Copyright © 2010 by American Scientific Publishers, Edited by Ahmad Umar and Yoon-Bong Hahn, ISBN: 1-58883-176-0

2 Umasankar Yogeswaran and Shen-Ming Chen, A Review on the Electrochemical Sensors and Biosensors Composed of Nanowires as Sensing Material, Sensors, 2008, 8, 290-313

3 Hernandez-Velez, M. Nanowires and 1D arrays fabrication: An overview. Thin Solid Films. 2006, 495, 51-63; DOI 10.1016/j.tsf.2005.08.331.

4 Tao Kong, Yang Chen, Yiping Ye, Kun Zhang, ZhenxingWang, XiaopingWang. An amperometric glucose biosensor based on the immobilization of glucose oxidase on the ZnO nanotubes, Sensors and Actuators B, 2001, 138, 344–350.

5 A. Kishen, M.S. John, C.S. Lim, A. Asundi. A fiber optic biosensor (FOBS) to monitor mutans streptococci in human saliva, Biosensors and Bioelectronics 18, (2003), 1371-1378

6 María Espinosa Bosch, Antonio Jesús Ruiz Sánchez, Fuensanta Sánchez Rojas, Catalina Bosch Ojeda. Recent Development in Optical Fiber Biosensors, Sensors 2007, 7, 797-859

7 J.S Rana, Jyoti Jindal, Vikas Beniwal, Vinod Chhokar Utility Biosensors for applications in Agriculture – A Review, Journal of American Science, 2010, 6(9), 353-375


in nanotechnology and biotechnology. The challenge is to create unique devices for detecting animal diseases, viruses and toxins using fundamental phenomena such as light absorbance, reflectance, transmittance, fluorescence and photoluminescence.Mutual research efforts, including cross-generation interactions, young researchers meetings and appropriate creative environment will grant necessary pre-conditions for sustainability of cooperation after the project is concluded. In total 164 secondment months are planned, 7 summer schools or training courses and 2 conferences.

Abstracts 21

GRIBAM; Gotheburg-Riga-Ion-Beam-Apparatus (Mobile), Design and First Results

J. Blahins1, A. Apsitis1, J. Klavins1, U. Berzinsh1, D. Hanstorp2

1Institute of Atomic Physics and Spectroscopy, University of Latvia. Riga, Latvia 2University of Gothenburg University, Gothenburg, Sweden

In this report we present the design and possible applications of an ion beam apparatus to produce a beams of atomic or molecular negative or positive ions. This activity is a collaboration between University of Latvia and University of Gothenburg within the European research Grant [1]. The long term goal is to investigate different atoms and ions of fundamental and astrophysical interest.Positive or negative ions are extracted from a plasma ion source (fillament type) and

accelerated with a high voltage (3-5kV). The ion beam is steered and shaped with ion optics, mass select using a (Wien filter) and charge exchanged in a cell containing a cesium vapour. The ions are then directed into an interaction chamber by help of an electrostatic quadrupole whereafter they enter the in-teraction region. The ion beam is finally detected using a Fara-day cup.One or more laser beams can be directed into interaction chamber parallelly or perpen-dicularly with respect to the ion beam. Electrons emitted in the photoinduced process can be detected perpendiculary to the beam by help of time of flight electron spectrometer using microchannel plate. The interaction region is construct-

ed using ultra high vacuum technology. (<<1E-9 Torr). There are some future ideas to increase an ion current, what today is <100 nA for positive ions and <10 nA for negative ions can be produced.GRIBAM is built on two mainframes on wheels, therefore the whole apparatus easily can be moved by means of a small van. Assembling of the apparatus can be performed in a few days time, so the apparatus can be moved to different sites where suitable lasers or synchrotron radiation is available. Thus the mobility is the main factor for a successful scientific program that will be conducted at GRIBAM.At the moment we work on experiment automating modules design on basis of LabView software and National Instruments DAQ cards and DIY made isolated field regulators. Ion optics modelling software SIM-Ion is used to maximize the gain.References: [1] Unlocking and Boosting Research Potential for Photonics in Latvia - Towards Effective Integration in the European Research Area (FOTONIKA-LV) /FP7-REGPOT-CT-2011-285912/

Fig. 1. The simplified scheme of apparatus


Solution-Processed Organic Bulk Heterojunction Bi-Layer Photovoltaic Cell with Non-Planar Phthalocyanine

I. Kaulachsa, G. Shlihtaa, P. Shipkovsa ,

A. Ivanovaa, M. Rozeb, A. Cielavsa

a Institute of Physical Energetics, 21 Aizkraukles Str., Riga LV-1006, LATVIA b Riga Technical University, 14 Azenes Str., Riga LV-1048, LATVIA

e-mail of presenting author: [email protected]

The bulk heterojunction approach appears to be one of the most promising concepts of creating efficient, low-cost and easily producible solar cells. For this purpose one of the best materials is regioregular poly-3-hexylthiophene (P3HT) which is widely used as a donor molecule and a hole transporter, with soluble fullerene derivative (PCBM) as acceptor and electron transporter. The main drawback of this highly efficient blend is its limited spectral range, covering only 350-650 nm interval. To extend the spectral range of this cell a second bulk heterojunction layer with complementary absorption spectra ought to be added in the cell. For this purpose non-planar phthalocyanines can be used as they have wide and strong intermolecular charge transfer absorption band in near infrared region. Therefore hydroxygallium phthalocyanine (GaOHPc) and PCBM blend are used as additional bulk heterojunction layer. Thus fully solution processed bi-layer photovoltaic cell (GaOHPc:PCBM/P3HT:PCBM) has been built by spin coating technique having high charge carrier photogeneration efficiency in 350-850 nm spectral range [1]. The spectral dependences of short circuit photocurrent external quantum efficiency (EQE) have been investigated in 350-1000 nm spectral range.The results of the research have shown that thermal annealing in vacuum at 100oC increases short-circuit photocurrent EQE values more than 2 times [1]. Different top electrodes of Al, In, Sm/Al and Yb/Al/Se were examined to achieve the best performance of our bi-layer cell. It was found that the best power conversion efficiency is provided by a Yb/Al electrode covered with a protective Se layer [1;2].

References[1] I. Kaulachs, I. Muzikante, L. Gerca, G. Shlihta, P. Shipkovs, G. Kashkarova, M. Roze, J. Kalnachs, A.

Murashov, J. Latvels, G. Rozite, 26th European Photovoltaic Solar Energy Conference and Exhibi-tion, 26th EU PVSEC proceedings on DVD, (2011) pp 601-604

[2] I. Kaulachs, I. Muzikante, L. Gerca, G. Shlihta, P. Shipkovs, V. Grehovs, J. Kalnachs, M. Roze, G. Roz-ite, A. Ivanova, Chemical Physics (2012), doi: http://dx.doi.org/10.1016/j.chemphys.2012.06.007

Abstracts 23

Applications of Laser Manipulation of Adiabatic States

A. Ekers1, N. Bezuglov1, 3, K. Miculis2 T. Kirova1, M. Bruvelis2, D. Efimov3, C. Andreeva1, 4, A. Cinins2, L. Kalvans2, M. Auzinsh2

1 Institute of Atomic Physics and Spectroscopy, University of Latvia, LV-1586 Riga, Latvia 2 Laser Centre, University of Latvia, LV-1002 Riga, Latvia

3 Faculty of Physics, St. Petersburg State University, 198904 St. Petersburg, Russia 4 Institute of Electronics, Bulgarian Academy of Sciences, 1784 Sofia, Bulgaria

The Autler-Townes effect is manifested when two levels are coupled by a strong coherent radiation field. When one of those levels is coupled by a weak probe field to a third level, the typical doublet can be observed in the probe excitation spectrum [1]. The present report reviews the hitherto results of Riga-group on possible applications of the Autler-Townes effect to the population switching and the resolution of hyperfine structure.The first part of the talk will consider a three-level system g-e-f coupled by two laser fields. If a strong laser field P is coupled between the levels g and e, then the excitation spectrum of level f obtained by scanning a weak probe field S across the e-f resonance does not exhibit the expected Autler-Townes doublet; instead, peculiar lineshapes are observed. These lineshapes can be explained by Ramsey-type interference of the laser-dressed (adiabatic) states. It will be discussed how such interference can be used in order to achieve switching of the population of level f via the variation of the S-field frequency. The second part of the talk will discuss the formation of dark states upon interaction of hyperfine level systems with strong laser fields [2]. Sodium 3S1/2, F’’=1, 2 and 3P1/2, F’=1, 2 levels are coupled by a strong S-laser field with Rabi frequency WS forming the adiabatic states. The latter are monitored by scanning a weak probe field across the 3P1/2, F’=1, 2 → 7D3/2 transition. The excitation spectrum of the 7D3/2 state shows the presence of an intense main peak with side peaks of much smaller intensities. The increase of WS shifts the side-peaks further apart, while the position of the main peak is hardly affected. These observations are explained in the adiabatic states formalism; depending on the S-field detuning either F’’=1 or F’’=2 component of the ground state is coupled to the two F’=1,2 levels of 3P1/2. We show that such system exhibits a visible “gray” state whose eigenvalue is weakly affected by the magnitude of WS. This gray state evolves into a dark state at high WS.We acknowledge the support by the EU FP7 Centre of Excellence project FOTONIKA-LV, the EU FP7 IRSES Project COLIMA, and the trilateral project supported by the Latvian, Lithuanian and Taiwanese research councils.

References[1] S. H. Autler and C. H. Townes, Phys. Rev., 100, 703 (1955).[2] J. S. Morris and B. W. Shore, Phys. Rev. A 27, 906 (1983).


The Development of Laser Pattern Generators from Single Beam in Rectangular Coordinates to Stamps

in Polar Coordinates

U. BerzinshInstitute of Atomic physics and Spectroscopy,

University of Latvia, LV-1586, Riga LATVIA

The report is based on authors long time experience in Micronic Laser Systems AB*1 the world leading producer and developer and of laser pattern generators. [1]. The pattern generators are applied in semiconductor industry and in display manufacturing successfully compete with electron beam writers since they are simpler, and faster, and cheaper. The presentation will quid you from first prototype designed in late 1980ies till latest model of Laser Direct Imaging writer what is under development and early installation phase in customer sites.The main principles will be presented for the different types of pattern generators developed with aim to achieve high speed, or high resolution, or large writing area, or high cost effectiveness. The large part of presentation will be dedicated to describe the innovative solutions of complex optical parts and modules, for example Spatial Light Modulators, Acousto Optic Modulators, Laser Systems, and Final Lenses. In order to demonstrate difference from fundamental research the examples will be demonstrated on research projects in high tech company were main goal is production. [2].

References[1] U. Ljungblad, T. Sandstrom, H. Bure, P. Dürr, H. Lakner, New Architekture for Laser Pattern Gen-

erators for 130 nm and Beyond. Proc of SPIE, Vol. 4186, pp. 16-21, (2001).[2] J. Heber, M. Wagner, P. Björnängen, J. Luberek, U. Berzinsh, T. Sandström, T. Karlin, Contrast

properties of spatial light modulators for microlithography. Proceedings of SPIE, Vol. 6730, pp. 673035-1 – 673035-10, (2007).

* Since 2010 Micronic Mydata AB

Abstracts 25

Multidetector Arrays Based on Wide Band Gap Crystals for X- and Gamma Rays Registration

A. Bulycheva, M. Shorohov, V. GostiloBaltic Scientific Instruments, Riga, Latvia

Multidetector structures, created on the one semiconductor crystal, like pixel, strip or coplanar greed arrays, have found wider application in imaging systems for X-ray medicine, gamma rays astronomy and technical areas. In the capacity of semiconductor crystal use the wide gape semiconductor crystals likes as CdZnTe and TlBr. These crystals are important material for the development of radiation detectors which have the advantages of a large absorption coefficient, compact size and room temperature operation.The semiconductor CdZnTe and TlBr crystals have a high values of charge carriers transport characteristics (the product of mobility by life time), high specific resistance, as well as high level of crystals homogeneity, lack of impurities, crystal borders, and twins. The quantity of contacts pads on one crystal can be up to hundreds and more. The assembly of detectors realizes by machine assembly. The most advanced contacting method is a flip-chip technology applying an indium or polymer bumps. Manufactured detectors have high spectrometric characteristics, low level of leakage current what avoid additional noises and high stability of the available characteristics in time. Spectrometric characteristics (energy resolution) measurements at room temperature average 2-3% and 14-15% at energies 59.6 keV and 5.9 keV for CdZnTe detectors and 3% and 9% at energies 59.6 keV and 5.9 keV for TlBr detectors respectively. CdZnTe and TlBr detectors are stable in time (do not change the characteristics).


Penetration and Toxicity of Nanoparticles in a Human Keratinocytes Cell Line and Human Skin Explants

S. Ahlberg1, F. Rancan1, A. Vogt1, J. Lademann1, C. Graf2, D. Neumann2, C. Greulich3, J. Diendorf 4, M. C. Meinke1

1 Department of Dermatology, Venerology and Allergology, Charité – Universitätsmedizin Berlin, Berlin, Germany,

2Department of Physics, Free University of Berlin, Berlin, Germany, 3Bergmannsheil University Hospital/Surgical Research, Ruhr-University Bochum,

Bochum, Germany, 4 Inorganic Chemistry and Center for Nanointegration Duisburg-Essen, University of

Duisburg-Essen, Essen, Germany Email: [email protected]

Nanoparticles (NPs) play an essential role in medicine, cosmetics and life science. It is still discussed which physicochemical properties enable nanoparticles to penetrate into the skin and reach the living cells. Skin Penetration is depending on different characteristics of the NPs like the material. Toxicity can be shown in form of reactive oxygen species (ROS) generation. In this presentation the interaction and toxicity of NPs like titanium dioxide and silver toward human keratinocyte cell line (HaCaT) and on excised human skin was investigated. The ROS production was investigated using different methods such as dichlorofluorescein assay and electron paramagnetic resonance (EPR) spectroscopy. The penetration of fluorescent labelled NPs into the living skin was investigated after application of the NPs onto the intact and barrier disrupted skin. After incubation dermis and epidermis were processed and digested to isolate and analyse skin cells using fluorescence activated cell sorting (FACS) and fluorescence microscopy. Another used method to see the penetration of single NPs in excised skin is X-ray microscopy. Using EPR spectroscopy free radical production in HaCaT could be measured after incubation with silver NPs. X-ray microscopy was applied to detect gold NPs in cryo sections and, for the first time, in its native form in a wet chamber. Especially barrier disrupted skin showed a penetration of NPs into the skin. Based on these different methods NPs can be investigated and knowledge about the interaction between NP and biological tissue can be obtained to calculate the risks with respect to the various possible applications of NP formulations.

Abstracts 27

Structural and Optical Properties of ZnO Nanostructures Deposited by Atomic Layer Deposition

Z. Alute1, R. Viter2, A. A. Chaaya3, M. Bechelany3, D. Erts1

1Institute of Chemical Physics, University of Latvia, Riga, Latvia 2Experimental physics department, Odessa National I.I. Mechnikov university,

Odessa, Ukraine 3European Institutes of Membranes, Montpellier, France

ZnO nanostructures had been deposited on silicon substrate with atomic layer deposition (ALD). The thickness of the samples varied from 20 to 200 nm. Structural properties of the samples were studied by AFM. The increase of the thickness stimulated the formation of crystallites with well shaped grains and transition from amorphous to crystalline state. The roughness of the surface has been calculated. It increased from 0.5 nm to 2.2 nm with the thickness growth. Optical properties of ZnO nanostructures had been investigated with reflectance spectroscopy and photoluminescence method. Optical band gap was calculated. The band gap energy was higher than for single crystal of ZnO (3.2 eV). For samples with 20 nm thickness no specific absorption edge was absorbed.Peak positions were calculated from photoluminescence spectra. UV and visible emission bands were observed. UV peaks corresponded to free exciton emission whereas visible emission was related to defect recombination centers. Low intensity was observed for samples with 20 nm thickness and no defect emission band was found.The analysis of structural and optical properties has been performed.


Resonance Raman Spectroscopy as a Non-Invasive Optical Method for Non-Direct Screening the Generation of Reactive

Oxygen Species in Human Skin

M. E. DarvinCenter of Experimental and Applied Cutaneous Physiology (CCP), Department of

Dermatology, Charité - Universitätsmedizin Berlin, Germany

The reactive oxygen species (ROS) are powerful reactive substances continuously produced on a mitochondrial level. Their oxidative activity is sufficient to oxidize DNA, lipids and proteins of living cells which can cause premature skin ageing and induce skin diseases including cancer. The amount of generated ROS is substantially enhanced following an increase in metabolism, inflammation, solar radiation, environmental hazards, etc.To combat the negative action of ROS, the human skin has developed a defence system comprising antioxidants like vitamins, carotenoids, enzymes. Various antioxidants possess a synergistic effect protecting each other from direct destruction when neutralizing ROS. Carotenoids are known to be effective quenchers of ROS. A reduction in their dermal concentration could be directly associated with the amount of generated ROS. Such measurements should be performed only in vivo.A recent non-invasive resonance Raman spectroscopy-based method has opened up wide possibilities to measure dermal carotenoids in vivo. Results show that the dermal carotenoids beta-carotene and lycopene, which have proven to be marker substances for ROS detection, are destroyed after UV and IR irradiation of the skin, following huge physical strain, inflammation-based illness, and smoking. The degradation of carotenoids after IR irradiation of human skin was a first indication of ROS formation which was later confirmed by electron paramagnetic resonance spectroscopy.

Abstracts 29

Multifuses Bbased on Polymer-Carbon Nanocomposites

K. DomkinNIIEMP, Penza, Russia

e-mail: [email protected]

Polymer multifuses (with up to 3000 switching without changing) now are widely used to protect electrical circuits against overcurrent and high temperature in transformers, electric motors, personal computers, automotive electronics, medical equipment, etc.The physical principle of operation of such systems is based on self-organization in supramolecular structures in phase transformations that occur near the melting point of the crystalline phase of the polymer. Thus, the transition of the crystalline phase to amorphous when heated to a very narrow temperature range is accompanied by a marked increase in its volume, the destruction of the spatial grid of conductive filler chains, resulting in a dramatic (up to 5 - 7 orders of magnitude) increase in the volume resistivity of polymeric nanocomposite (posistor effect).The reverse process takes place during cooling of these systems leads to the restoration of the former space of the supramolecular structure of the conductive chains of filler and an abrupt decrease in volume resistivity of the material to its original level.Multifuse elements are made of conductive plastic, molded into a thin sheet with electrodes on both sides. The electrodes ensure even distribution of energy over the surface area. Wire soldered to the electrodes, or lobe findings.The temperature dependence of the resistance produced samples were investigated at various stages of manufacture to the installation of monitoring the temperature dependence of resistance of multifuses.


Dynamics of Excitonic Complexes in Single InGaN Quantum Dots

M. O. Eriksson1, Chih-Wei Hsu1, E. S. Moskalenko2, A. Lundskog1, S. Amloy1, K. F. Karlsson1, P. Bergman1, E. Janzén1, P. O. Holtz1

1 Department of Physics, Chemistry and Biology (IFM), Linköping University, 581 83 Linköping, Sweden

2 A. F. Ioffe Physical-Technical Institute, RAS, 194021, Polytechnicheskaya 26, St. Petersburg, Russia

Optical properties of InGaN quantum dots (QDs) on GaN pyramids, grown using hot wall metal organic chemical vapor deposition, have been characterized by photoluminescence spectroscopy techniques. A thin layer of InGaN has been grown on µm-sized hexagonal GaN pyramids and capped by GaN. Truncated pyramid apices can host InGaN QDs, which have been studied.[1] InGaN QDs formed by potential fluctuations in a GaN/InGaN/GaN quantum well (QW) grown by plasma-assisted molecular beam epitaxy have also been studied.[2] Micro-photoluminescence (µPL) spectroscopy (laser spot size of 1-2 µm) measurements on pyramids separated by several µm have enabled the study of single InGaN QDs, which are evidenced by sharp spectral peaks around 3.0-3.1 eV. For the sample with InGaN QDs in a QW, excitation of single QDs has been enabled by focusing the laser on the sample through sub-µm openings in a mask on the sample. Extensive PL spectroscopy analyses have been conducted to identify single excitons, biexcitons,[2] and charged excitons[1] in the InGaN QDs. TRµPL spectroscopy performed on single neutral excitons indicate exponentially decaying photoluminescence intensities with increasing time, in agreement with the expected dynamics of such excitons. Various excitonic complexes with lifetimes in a range from 100 ps to 1 ns have been monitored. The charged exciton and the biexciton have about half as long lifetimes as the corresponding single neutral exciton in the respective QD. The TRµPL study gives insight into the dynamics of excitonic complexes in InGaN QDs, as well as providing essential information for the identification of the excitons.

References[1] Chih-Wei Hsu, et. al., Single Excitons in InGaN Quantum Dots on GaN Pyramid Arrays, Nano Let-

ters, 2011.[2] Supaluck Amloy, et. al., Polarization-resolved fine-structure splitting of zero-dimensional Inx-

Ga1-xN excitons.

Abstracts 31

Levitation and Manipulation of Aerosol Particles by Radiation Pressure

O. Isaksson1, 2, V. M. Ando2, M. Karlsteen1, D. Hanstorp2

1 Chalmers University of Technology, SE-412,96 Gothenburg, Sweden 2 Department of Physics, Gothenburg University, SE-412,96 Gothenburg, Sweden


In the seventies, Arthur Ashkin [1,2] showed that particles can be levitated using radiation pressure. We have, using a similar technique, been able to levitate a single oil-drop for approximately four hours. The drop was levitated just above the focus formed by a 30 mm lens in a vertically oriented laser beam. It was allowed to fall down through the laserbeam and it was trapped at the point where the radiation pressure balanced the gravitational force. This required a laser power of approximately 900 mW. The goal of our experiment is to show that we can measure the charge to mass ratio of the levitated oil drop. The levitation takes place inside a cell, Fig\ref{Figure 1 levitation}.An electric field is applied between two electrodes in the bottom and the top of the cell. The charged drop is forced to oscillate by applying an AC electric field between the two electrodes. The movement is visualized by imaging the drop on a screen placed 1 m away from the cell, where the oscillations are magnified to an amplitude of a few millimetres. The intense scattering from the drop produces an image that is easily observable by the bare eye.

References[1] A. Ashkin, Acceleration and trapping of particles by radiation pressure, Physical Review Letters,

24, s.156-159, (1970)[2] A. Ashkin, Optical Levitation by Radiation Pressure, Applied Physics Letters, 19, s. 283, (1971)


Skin Hemoglobin Assessment by Spectral Imaging

D. Jakovels, I. Kuzmina, A. Berzina, J. SpigulisUniversity of Latvia, Institute of Atomic Physics and Spectroscopy

Optical imaging technologies are used for non-invasive assessment of skin blood supply. Laser Doppler perfusion imaging and laser speckle imaging are commercially available techniques for mapping of microvascular perfusion in tissue [1]. Multi-spectral imaging (MSI) has shown potential for mapping of skin chromophores, e.g. oxy-/deoxy-hemoglobin and melanin [2]. Such mapping ensures reliable non-invasive evaluation of skin condition and can be used for evaluation of vascular malformation treatment [3].Multi-spectral imaging was provided by halogen lamp ring-light illumination and liquid crystal tunable filter (LCFT) acquiring 51 images in spectral range 450 – 950 nm with spectral resolution 10 nm. Visible spectral range 500 – 700 nm was selected for evaluation of skin chromophore changes. The system was approbated in laboratory by arterial and venous occlusion tests. Clinical trial was performed by monitoring vascular malformations laser treatment.Besides, RGB imaging system for mapping and monitoring of hemoglobin distribution in skin has been designed and tested. RGB sensor can be regarded as a simple and fast MSI device acquiring three spectral (red (R), green (G) and blue (B)) images simultaneously. In combination with specific narrow-band spectral light sources RGB imaging could become competitive for some specific applications, including the assessment of skin chromophore concentration [4, 5].

References[1] J.D. Briers, Laser Doppler, speckle and related techniques for blood perfusion mapping and im-

aging, Physiol. Meas. 22(4), R35–R66 (2001).[2] D. Jakovels, J. Spigulis, 2-D mapping of skin chromophores in the spectral range 500-700 nm, J.

Biophoton. 3(3), 125-129 (2010).[3] I. Kuzmina, I. Diebele, J. Spigulis, L. Valeine, A. Berzina and A. Abelite, Contact and contactless

diffuse reflectance spectroscopy: potential for recovery monitoring of vascular lesions after in-tense pulsed light treatment, J. Biomed. Opt. 16, 040505 (2011).

[4] I. Nishidate, K. Sasaoka, T. Yuasa, Visualizing of skin chromophore concentrations by use of RGB images, Opt. Letters b, 2263-2265 (2008).

[5] D. Jakovels, J.Spigulis, RGB Imaging Device for Mapping and Monitoring of Hemoglobin Distribu-tion in Skin, Lith J Phys, Vol. 52, No. 1, pp. 50–54 (2012).

Abstracts 33

Photonics Results Applied in GNSS and Geoid Determination

I. Janpaule, D. Haritonova, K. MorozovaUniversity of Latvia, Institute of Geodesy and Geoinformation

The photonics plays an important role at the research and develpment of the Institute of Geodesy and Geoinformation of the University of Latvia (LU GGI). The LU GGI applies the space related technologies for the environmental studies in Latvia. Photonics has been applied in satellite laser ranging (SLR) system for Low Earth Orbiters (LEO) operational at the GGI. Test observations have approved the capability of SLR for LEO ranging, including LAGEOS, ERS2, ENVISAT, Ajisai and others. Recently the development and testing of a new digital zenith camera model and it’s control software for the studies of vertical deflection has been commenced in GGI. Application of photonics instrumentation kas a key function for star image acquisition. Main objective of the project – multiple improvement of data acquisition for accurate geoid model, widely used in ingeneering application. The impact of the Earth tides on the coordinate changes of EUPOS®-RIGA and EPN stations has been studied. EUPOS and EPN reference stations have been used and Bernese v.5.0 software in kinematic mode was applied. Earth tides and the tide caused deformations of the Earth crust create vertical movement of the site with the maximum amplitude of 30 cm according to the theoretical estimates. The standard data sets were taken from IGS data base. Earth tidal vertical displacements at GNSS stations have been obtained by modifying the routine of Bernese GPS Software computing tidal station displacements in accordance with the latest IERS Conventions. The positioning accuracy was discovered as well.


Groupwise Shape Registration Based on Entropy Minimization

Y. Kee1, 2, D. Cremers2, J. Kim1

1 Korea Advanced Institute of Science (KAIST) 2 Technical University Munich

In this work, we propose a global-to-local groupwise shape registration based on entropy minimization. We introduce the information-theoretic concept of entropy as an energy functional for shape registration. To this end, for given example shapes, we estimate the underlying shape distribution on the space of signed distance functions in a nonparametric way. We then perform global (similarity) shape registration by minimizing the shape entropy, which is followed by the local (nonrigid) registration minimizing entropy of displacement vector fields between a template shape and the globally registered shapes. The template shape is estimated using the curve evolution theory based on the gradient flow of shape entropy which is explicitly derived using L2-distance. Lastly, diffeomorphisms which are estimated by both of rigid/nonrigid registrations obviously establish dense correspondences between an example shape and the template shape. Moreover, the composition rule gives a way to establish consistent correspondences among the example shapes by guaranteeing another diffeomorphism. One limitation of this work is that the template shape is not unique because the differential entropy can go to negative infinity. Although we introduce a hard constraint not to let the density estimate converge to the Dirac delta function, the future work should be focussed on identifying more principled solution. For this reason, future work is to gradually get rid of the template shape estimation process and unify our framework into the groupwise registration in a simultaneous manner – we suppose this framework can give a probabilistic shape model for object recognition.

Abstracts 35

Basal Plane Stacking Faults Related luminescence in ZnO Nanostructures

V. Khranovskyy, L. Hultman, R. YakimovaLinköping University, Department of Physics,

Chemistry and Biology, 583 81 Linköping, Sweden

ZnO is a wide band gap semiconductor (Eg ≈ 3.37 eV) with a strong prospective for optoelectronic, photonic and plasmonic applications. Nominally, ZnO crystallizes in a wurtzite structure (WZ) but under specific growth conditions a basal plane stacking faults (BSFs) may be introduced. BSFs in the materials of wurtzite structure, such as GaN and ZnO, can be considered as a sheet of zinc blend structure embedded in the wurtzite structure and are expected to strongly affect the PL spectrum. Moreover, the periodical multiply BSFs could be considered as a coupled quantum well structure. The photoluminescence of ZnO nanowires with a priori high density of basal plane stacking faults (BSFs) is studied in comparison to BSFs free ZnO nanostructures. The BSFs of density ~5·105 cm-1 result in additional peak at 3.329 eV on the PL spectrum of ZnO at 4 K. The mechanism of emission is explained as indirect exciton transition from quantum wells electrons in conduction band recombining with holes, localized at BSFs. The QW electrons binding energy in the cubic ZnO was estimated to be ~100 meV, while the holes binding energy was ~5 meV, which is explained as due to periodic location of BSFs with rather small distance in-between (~20 nm), thus forming a quantum well-like structure. The data obtained are compared to similar phenomena that have recently been reported in GaN, InGan, AlGaN as well as single and multiply quantum wells structures.


The Effect of Solution Spraying Rate on the Properties of Chemically Sprayed ZnO:In Thin Films

M. Kukk, M. Kriisa, E. Kärber, M. KrunksDepartment of Materials Science, Tallinn University of Technology

Fabrication of transparent and conductive ZnO thin films by different methods is broadly studied. Among chemical deposition methods the chemical spray pyrolysis is an attractive low cost technique to obtain metal oxide thin films. The method has a lot of parameters which have effect on the resulting films optical and electrical properties, e.g. precursor salt and its concentration, growth temperature, dopant concentration, etc.In this work we study the effect of solution spraying rate (varies from 0.52 to 6.7 ml/min) on the structural, optical and electrical properties of ZnO:In films that were deposited by chemical spray pyrolysis from zinc acetate solutions containing 3 at.% of InCl3.Films were characterized with X-ray diffraction and optical transmittance and reflectance spectra. Electrical resistivity, carrier concentration and mobility were determined by van der Pauw and Hall measurements.With an increase in spraying rate from 0.5 up to 3 ml/min, the resistivity decreases rapidly (from 60 to 3 mΩ·cm). Carrier mobility and concentration increase from 4 to 15.5 cm2/Vs and from 2.2·1019 to 1.4·1020 cm-3, respectively. Further increase in spraying rate increases the resistivity and decreases mobility and concentration of carriers. A decrease in transmittance in the NIR region has been observed due to the higher number of charge carriers in films deposited at higher spraying rates.We conclude that besides the growth temperature and doping level of the films, solution spraying rate is also an important parameter witch impacts considerably the optical and electrical properties of ZnO films obtained by chemical spray pyrolysis.

Abstracts 37

Photonics Technologies in Astrospectroscopy

A. LaureUniversity of Latvia, Faculty of Physics and Mathematics,

Raiņa bulvāris 19, LV-1586, Rīga, Latvia

This research is based on high-resolution spectroscopy of proto-planetary nebulae.The science of photonics includes the detection of light and it covers all the technical applications of light over the whole spectrum from ultraviolet over the visible to the far-infrared.One of the applications where light detection (photonics) is used is astrospectroscopy – technique of spectroscopy used in astronomy. The object of study is the spectrum of electromagnetic radiation, including visible light, which radiates from stars and other celestial objects. Spectroscopy can be used to derive many properties of distant stars and galaxies, such as their chemical composition, but also their motion by Doppler shift measurements. Most stellar spectra share these two dominant features of the Sun’s spectrum: emission at all wavelengths across the optical spectrum (the continuum) with many discrete absorption lines, resulting from gaps of radiation.This research object is proto-planetary nebulae IRAS22272+5435. Proto-planetary nebulae is the transition phase between AGB (asymptotic giant branch) and planetary nebulae, when large mass-losses stopped, but the star is not hot enough to emit Lyman continuum photons, to ionized dropped surrounding envelope of AGB star and become a planetary nebulae.Our work is based on time-series observations between 2002 and 2011 and Spectra were taken from Peak Terskol Observatory located in the Northern Caucasus at an altitude of 3100 m. High-resolution spectra for IRAS22272+5435 were obtained with the coudé échelle spectrometer MAESTRO (R ~ 45,000) on the 2m telescope. There were used CCD for spectra detection. Backside illuminated chip was used in 2006 and 2008 therefore the spectra longward of about 6700 Å are significantly affected by interference fringes.


Optical Approach for the Express Registration of Total Toxicity of Environmental Objects

I. Pylypenko1, N. Starodub2

1 National Academy of Foods Technology, Ukraine 65039, Odessa, Kanatnaja Str., 112, e-mail: [email protected]

2 National University of Life and Environmental Sciences, 15 Herojev Oboroni Str., Kyiv, 03041 Ukraine,


Chronic mycotoxicosis presents real danger for human and animal health. Mycotoxins may be revealed in different types of corn, vegetables, fruits and foodstuffs. For the prevention of non-desirable effects which may be appeared in case of microscopic fungi growth the main role belongs to prophylaxis through the regular control of the toxin concentration. It may be realized in case of the providing of practice by the analytical devices which have very high selectivity, sensitivity and are able to fulfill express analysis in field condition and on line regime. In this report the experimental data about the determination of the total toxicity (as first step of food and feed control) by the optical biosensors based on the application of chemiluminescence (ChL) of Daphnia magna living media (ChL-test) and bioluminescence (BL) of bacteria (BL-test) will be presented. D. magna was obtained accordingly to International standard. The density of culture was 5 of person in 10 cm3. ChL was registered in the presence of living medium, luminal and H2O2. Phosphorescenum phosphorescenum Sq3 strain was isolated from Sea of Azov. The density of bacterial suspension was 5x105cells/ml. The registration of BL was accomplished thought 20-90 min in dependence on type and concentration of mycotoxins. For this purpose it was developed the special portable device. Investigations were fulfilled with patulin and T2 mycotoxin as most dispersed and toxic substances. The developed optical biosensor systems are able to provide all practice demand in the respect of sensitivity of analysis, its simplicity and rapidity at the screening environmental objects on total toxicity including that which may be stipulated by the presence of mycotoxins.

Abstracts 39

Resonances and Threshold in Negative Ion Photodetachment

J. RohlénUniversity of Gothenburg


Negative ions are of considerable interest in atomic physics since their properties are strongly influenced by electron-electron correlation. Experimental investigations can therefore serve as benchmarks for atomic many-body calculations. In this respect, two-electron processes in negative ions are of specific interest. Such processes include excitation and decay of doubly excited states and photodetachment into excited states of the residual atom. We have recently presented a method with which it is possible to measure partial photodetachment cross sections to highly excited states in the residual atom. Cs- photodetachment have been investigated in a yet unpublished study. Four partial cross sections from this experiment will be presented. To analyze the complicated structures in the data it is important to take the interaction of the resonances with each other into account. A model for extraction of resonance parameters which includes such interaction will be described. The new detection method led to the first observation of a detachment threshold where the shape of the cross section is determined by the large and negative polarizability of the residual atom. In the Cs- study the complex resonance structure impede any detailed investigation of the non resonant cross sections. An attempt to observe clean thresholds in Na- photodetachment is underway. The progress of these experiments will be discussed together with possible implications of the data obtained from Cs-.


Experimental Examination of Efficiency of Express Control of Horse Chestnut Tree State by Portable Optical Instrument

K. Shavanova, N. StarodubNational University of Life and Environmental Sciences of Ukraine

15 Heroyiv Oborony St., Kyiv, 03041 Ukraine e-mail: [email protected]

Today more than two million horse chestnut trees are growing at the territory of Kyiv as ornamentals. Incidentally, the horse chestnut leaves and blossom used to feature on the coat of Kyiv arms. In previous years the chestnuts began to turn yellow and lose leaves in late July, and this year in mid-June some trees had completely withered foliage. The intensity of chlorophyll fluorescence depends on photosynthetic activity. After irradiation of leaf the intensity of chlorophyll fluorescent signal is increasing at first and then slowly reduces. This effect is called as effect of Kautsky or effect of chlorophyll fluorescent induction (CFI). The form of this curve is very sensitive to adverse environment. It gave possibility to develop in the V.M. Glushkov Institute of Cybernetics of NAS of Ukraine the portable device “Floratest”, which lets to estimate in several seconds the plant state without plant damage. In 2010-2011 experimental researches of portable device “Floratest” were carried out to detect influence of horse chestnut (Aesculus hippocastanum L.) major pathogens on the plants state in Kyiv. Preliminary researches indicate that portable device “Floratest” can be used for detecting of Cameraria ohridella Desch. & Dim. and Guignardia aesculi (Peck) Stev. influence on state of plants by measuring of CFI curve. The form of CFI curve changes versus level of harmful substances influence. On basis of preliminary researches there were shown that using of portable device «Floratest» let to detect in express mode the worsening of photosynthetic apparatus of plant by measuring fluorescence of native chlorophyll on the early stages.

Abstracts 41

Complex of Chlorin e6 and Quantum Dots Coated by Different Phospholipids: Stability and Spectral Properties

A. Skripka1, J. Valančiūnaitė2, R. Rotomskis2

1 Institute of Oncology Vilnius University, Baublio 3b., LT-08406, Vilnius, Lithuania 2 Faculty of Physics, Vilnius University, Saulėtekio ave. 9, bldg. 3, LT-10222 Vilnius, Lithuania


Here the stability and spectral properties of CdSe/ZnS quantum dots (QDs) (625nm) coated by different phospholipids in aqueous solution (PB pH 7) is presented as well as the interaction with photosensitizer chlorin e6 (Ce6).The surface of hydrophobic QDs was modified using different phospholipids containing saturated and unsaturated fatty acids. QDs were successfully solubilized by saturated PEG-DPPE and unsaturated PEG-DOPE, although the colloidal stability of such QDs was poor. An attempt to solubilize QDs using PEG free unsaturated phospholipids (DOPC) was ineffective. Further, mixing DOPC with either PEG-DPPE or PEG-DOPE resulted in effective solubilization of QDs in aqueous solution. While QDs encapsulated into DOPC:PEG-DOPE micelles with molar ratios of 1:1 and 2:1 showed long term colloidal stability in aqueous solution, the colloidal solution of QDs modified by DOPC:PEG-DPPE (molar ratio 2:1) was unstable. The modification of QDs surface with different phospholipids had no effect on the absorption spectra of QDs compared to the absorption spectrum of QDs in toluene. However, some decrease in the quantum yield of QDs photoluminescence was observed after modification. The formation of QD-Ce6 complex was observed by adding a small amount of concentrated Ce6 solution to QDs solution obtaining QD:Ce6 molar ratio 1:5. Observed spectral changes indicate that QD-Ce6 complex can only be formed with QDs encapsulated with unsaturated phospholipids. Efficient energy transfer from QDs to bound Ce6 molecules is achieved due to close localization of the Ce6 molecules to the core of QDs which is crucial for its further application in photodynamic therapy of cancer.

This work was supported by a grant (No. MIP-095/2011) from the Research Council of Lithuania.


Fluorescent Gold Nanoclusters for X-Ray Imaging

A. Šlėktaitė1, R. Kubiliūtė1, R. Rotomskis1, 2

1 Laboratory of Biomedical Physics, Scientific Research Center, Institute of Oncology, Vilnius University, Baublio 3b, LT-08406, Vilnius, Lithuania

2 Biophotonics group of Laser Research Center, Vilnius University, Saulėtekio 9, LT-10222 Vilnius, Lithuania


Diagnosis of cancer at an early stage is very important, because it allows more efficient therapy. Currently the most efficient cancer diagnostic method is X-ray and one of the ways to improve X-ray imaging is usage of contrast agents. Gold, due to greater atomic number, gives higher X-ray attneuation rate than currently used X-ray contrast agent iodine [1]. Also, gold nanoparticles possess the properties of low toxicity, long-term presence in the blood circulation system, and easy surface functionalisation [2,3]. Therefore, gold nanoparticles have the potential to be effective X-ray contrast agent. The purpose of this work was to synthesise fluorescent gold nanoparticles, evaluate their optical properties and potential to be used as an X-ray contrast agent.Gold nanoparticles were synthesised using chloroauric acid and 2-(N-morpholino)-ethanesulfonic acid (MES) buffer [4] at different pH values. These colloids presented pH dependant absorption spectra. Fluorescence of the particles yielded single band at 480 nm wavelength and fluorescence excitation yielded band at 420 nm. With different pH values only amount of formed particles varied. Most efficient synthesis reaction was reached at pH 6,3. Synthesised particles were concentrated and their X-ray contrast was observed using standard mammographic unit at 20 kVp energy and 50 mAs exposition. Experiments were performed in vivo with two mice bearing hepatoma in a right thigh. Nanoparticles could be tracked in mice’s bodies with sufficient contrast intensity. In conclusion, MES stabilized gold nanoparticles presented adequate X-ray contrast intensity as iodine based contrast mediums and after some alterations could be used as a contrast agent.

References[1] Hubbell J., Seltzer S. Tables of X-Ray Mass Attenuation Coefficients and Mass Energy-Absorption

Coefficients from 1 keV to 20 MeV for Elements Z = 1 to 92 and 48 Additional Substances of Dosimetric Interest Ionizing Radiation Division, Physics Laboratory, NIST, USA, 1996.

[2] Yeh H., Sharma J., Yoo H., Martinez J., Werner J. Photophysical Characterization of Fluorescent Metal Nanoclusters Synthesized Using Oligonucleotides, Proteins and Small Reagent Molecules. Proceedings of Bios SPIE Photonics West: Reporters, Markers, Dyes, Nanoparticles, and Molecu-lar Probes for Biomedical Applications II, San Fransisco, California, USA, 2010, 7576, p. 75760N.

[3] Hainfeld J., Slatkin D., Focella T., Smilowitz H. Gold Nanoparticles: a New X-ray Contrast Agent. Br. J. Radiol., 2006, 79 (938), p. 248–253.

[4] Alric C., Taleb J., Le Duc G., Mandon C., Billotey C., Le Meur-Herland A., Brochard T., Vocanson F., Janier M., Perriat P., Roux S., Tillement O. Gadolinium Chelate Coated Gold Nanoparticles as Contrast Agents for Both X-ray Computed Tomography and Magnetic Resonance Imaging. J. Am. Chem. Soc., 2008, 130, p. 5908–5915.

[5] Bao Y., Yeh H., Zhong C. Bao Y, Yeh H.-C., Sharma J., Zhong C., Neidig M., Vu D.M., Dyer R.B., Shreve A.P., Werner J.H., Martinez J.S. Formation and Stabilization of Fluorescent Au Nanoclus-ters Using Small Molecules. J. Phys. Chem., 2010, 114 (38), p. 15879-1588

Abstracts 43

Structured Nano-Porous Silicon as Transducer of Immume Biosensor at the Control of Mycotoxins

S. N. Flyshyk, N. F. StarodubNational University of Life and Environmental Sciences,

15 Herojev Oboroni Str., Kyiv, 03041 e-mail: [email protected]

Mycotoxins presented by T2, patulin are widespread and characterized by high level toxicity. To meet all the requirements of practice in respect of high sensitivity of analysis we propose to use of structured nano-porous silicon (sNPS) as transducers for the immune biosensors with the registration of the specific signal on the basis of changes of chemiluminescence (ChL) or photocurrent of this structure. The analysis was carried by “direct” way when specific antibodies (Ab) were immobilized on the sNPS surface and then they reacted with appropriate mycotoxins in model solution.It was used boron doped single-crystal silicon square wafers with resistivity of 1 Ohm×cm, with area of 100 cm2 thickness of 0.3 µ m. The surface of the wafers was not polished. sNPS layers were prepared by stain etching in HF: HNO3 solution at the room temperature, natural day-time illumination and time duration from 1 to 20 min. Thickness of sNPS layer changed from 3 up to 60 nm, was supervised by parameters of technological process at chemical modification of a surface of single-crystal silicon and defined with the help of Auger electronic spectroscopy at the LAS-2000. The structure of sNPS surface was studied using scanning tunnel microscope (STM) and scanning electron microscope. Analysis of the obtained images of the surface shows that of the sNPS surface is regularly covered by nano-scale hills up to 20 nm high. It was shown that the sensitivity of such biosensors allows determining T-2 mycotoxin and patulin at the concentration of 10 ng/ml during several minutes.


Referencing Satellite Data with LIF and SFS Technique in the Multi-Tier Monitoring Model

I. SobolevTallinn University of Technology e-mail: [email protected]

The modern tasks of cleanup and recovery in case of marine oil spill impose high requirements on technologies for the detection and monitoring of water objects. The detailed real-time data with high spatial resolution is required for rapid response. On the other hand it is necessary to have full information about the spill location and dimensions for strategic planning and early warning capabilities. Above requirements are combined into one model of Multi-Tier Monitoring. In this concept the detection of anomaly dimensions and location using far looking satellite data provide the first tier. The airborne active FLS®-Lidar is considered as the middle tier with high spatial (less than 10 m) and spectral (less than 5 nm in UV/VIS spectral ranges) resolution. The lower tier is anchored with the geographical locations of important findings detected at the middle tier. Taken water samples are analyzed with fast-screening technology of Spectral Fluorescence Signatures (SFS) giving more analytical qualitative and quantitative results. Latter allows calibrating the Lidar data for oil type, aggregate state (film, emulsion) and weathering status information. Precisely geo-referenced LIF (Laser Induced Fluorescence) data of hyperspectral FLS®-Lidar allows detection of pollution incidents and mapping of environmental trends over vast water systems like coastal zone, lakes and rivers.

Abstracts 45

Effect of Induction of Chlorophyll Fluorescence as Express Approach for Diagnostics of General State of Plants

R. Son’ko, N. StarodubNational University of Life and Environmental Sciences,

Heroyiv Oborony st., 15, Kyiv-03041, Ukraine

Plants during their growing and vegetation are under constant influence of different environmental factors many of which may have negative consequences for the viability of the organism. The study of the peculiarities of these processes under the influence of environmental factors makes it possible to quickly assess the deteriorating condition of the plants before the external manifestations. One of approaches to diagnosis is the assessment of indicators of chlorophyll fluorescence induction (IFCh). Its essence is to estimate the radiation absorbed by plants of light energy as fluorescence. The processes of photosynthesis and IFCh are competitive, so the suppression of one of them leads to an increase in the other, which is as the basis for obtaining diagnostic criteria.We used IFCh to diagnose changes in the photosynthetic chain of winter wheat after treatment with herbicide, “Logran”. Measurements of IFCh were made using the fluorometer, developed at the V.M. Glushkov Institute of Cybernetics of NAS. As a result of our investigations it has shown that the introduction of the minimal recommended quantities of the herbicide leads to changes in the process of photosynthesis. The herbicide has increased the background level of fluorescence of chlorophyll, due to increased losses of energy excitation during its migration trough the pigment matrix, and a violation of a functional connection with the reaction centers. It was also found deterioration processes of the light stage of the photosynthesis, resulting in a decreasing in activity electron-transport chain of the photosynthetic apparatus, as well as reduction of active complexes and efficiency of photochemical reactions of photo system II.


Quantum Dots as Drug Delivery System for Phallotoxin

K. Stašys1, V. Karabanovas1, R. Rotomskis1, 2

1 Laboratory of Biomedical Physics of Vilnius University institute of Oncology, Lithuania 2 Department of Physics, Vilnius University, Lithuania


Semiconductor nanoparticles known as quantum dots (QD) are very promising in biomedical apllications due to their unique photophysical properties such as wide absorption and narrow emission bands. In order to use QD for cellular visualization and cancer treatment including drug delivery systems, it is vital to understand the fundamental mechanisms of their entrance and trafficking within cells. Before this could be done, QD surface has to be modified using specific ligands in order to make them hydrophilic and able to pass through cell membrane. After modification of QD surface with different thiols we observed that mercaptorpopionic acid (MPA) is most suitable for QD surface modification. In previous works [1] it is shown that the best QD surface ligand is QD-MPA retains high colloidal stability and good optical properties. We also showed that QD-MPA enter cells by endocytotic pathway but does not affect cells viability. However if we want to use quantum dots as nanoplatform for drug delivery additional information is needed.The goal of our study was to investigate how QD and their phallotoxin conjugates ac-cumulate in mouse embryo fibroblast cells (NIH3T3) by using fluorescence confocal mi-croscopy. Phalloidin was selected as phallotoxin which is isolated from the deadly Ama-nita phalloides mushroom and is commonly used in imaging applications to selectively label F-actin in fixed cells, permeabilized cells, and cell-free experiments. Therefore, this dye does not work on living, nonfixed cells and do not pass the cell membrane. In this work, we used QD-MPA with 625 nm emission band and Alexa Fluor 488 Phalloidin conjugate with 488 nm emission band. QD-MPA and phalloidin was mixed together to create one conjugate in order to investigate if QD can be used as drug carriers.

Fig. 1. NIH3T3 cell after 24 h incubation with QD-MPA (red) and cell nucleus is marked with DAPI (blue) (A). NIH3T3 cell with QD-MPA (red) and Alexa Fluor 488 Phalloidin (green) conjugate after 24 h incubation (B).

As shown in Fig. 1A,B QD-MPA and QD-MPA-phalloidin conjugates successfully accumulate in NIH3T3 cells after 24h of incubation. However, QD-MPA accumulate only

Abstracts 47

in late endosomes while QD-MPA-phalloidin conjugates pass into cell and separately Alexa Fluor 488 Phalloidin conjugate labels actin filaments and QD pass to cell nucleus. These results show that QD-MPA can be used as phalotoxin delivery system. Although, QD-MPA accumulation in cell nucleus suggests that phalotoxins affect cell viability and inner processes which results in the change of nucleus membrane permeability. All in all, this phallotoxin delivery system is a great breakthrough in creating an universal QD based drug delivery systems which will change the modern medicine as we know it and greatly improves cancer treatment.

References[1] Stašys K, Karabanovas V, Rotomskis R, Valius M. Surface modification of (CdSe) ZnS quantum

dots using thiols – characterization, photophysical and biological studies. Medical Physics in the Baltic States: proceedings of the 8th international conference on medical physics. Kaunas, Lithuania. 2010, 2:77–81.


Photoluminescence Immune Biosensor for Salmonella Detection, Based on TiO2 Nanowires

Alla Tereschenko1, Roman Viter1, Nikolay Starodub2, Yulia Ogorodniichuk2, Valentyn Smyntyna1

1 Odessa National I.I. Mechnikov University, 42, Pastera, 65026, Odessa, Ukraine 2 National University of Life and Environmental Sciences, 15, Heroyiv Oborony, 03041,

Kyiv, Ukraine

A novel method for Salmonella detection using photoluminescence immune biosensor, based on TiO2 nanowires, is proposed. TiO2 nanowires were solved in ethanol and then deposited on glass substrates. To fabricate biosenstitive layer, salmonella antibodies were solved in water (0.25 mg/ml) and then immobilized on the surface of TiO2 NWs. Photoluminescence (PL) spectra of titania nanowires were measured in the range of 370-800 nm (excitation with Nd:YAG solid state laser, excitation wavelength 355 nm) before and after immobilization of salmonella antibodies. It was found that adsorption of salmonella antibodies resulted in increase of PL intensity and 10 nm shift of peak position to shorter wavelengths. The biosensor is based on specific immune reaction between antigens and antibodies of salmonella. Water solutions of Salmonella antigens were prepared in the concentration range from 102 to 106 cl/ml. Reaction of salmonella antigens with immune biosensor supported with decrease of PL spectra and peak position shift to longer wavelengths. Calibration curve of biosensor signal versus Salmonella antigens concentration was plotted. The immune biosensor can determine salmonella antigens at the range of 103 to 105 cl/ml. Sensitivity mechanism is proposed.

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PROGRAMME - LU · 2015-02-05 · 1st International Conference “Photonics Technologies – Riga 2012” 3 Programme for the Training Course 23-25 August, 2012 Thursday, 23 August