Institute of Applied Research

Institute of Applied Research

Sukurta: 11 September 2013

tmi

9 Saulėtekio, LT-10222 Vilnius
Tel./fax 236 6059
E-mail:
www http://www.tmi.vu.lt

Director – Prof. Habil. Dr. Saulius Antanas Juršėnas

STAFF

31 research fellows (23 holding research degree)

MAIN RESEARCH AREAS OF THE INSTITUTE

Semiconductor Physics, Electronics and Optoelectronics
Laser Physics and Light Technologies
New Materials, Nano-structures and Surfaces: Synthesis, Characterization, Technologies
Informatics and Technologies of Information Society

DOCTORAL DISSERTATIONS MAINTAINED IN 2013

M. Karaliūnas. Investigation of zinc oxide based heterojunction structures for optoelectronic devices by means of spectroscopy methods.

G. Manolis. Optical and electrical properties of highly excited 3C SiC crystals and heterostructures.

D. Dobrovolskas. Study of carrier dynamics in InGaN using spatially-resolved photoliuminescence techniques.

A. Miasojedovas. Control of fluorescence properties of organic optoelectronic materials by molecular aggregate formation.

P. Ščajev. Investigation of wide-band-gap semiconductor photoelectric properties by using optical techniques with temporal and spatial resolution.

DEPARTMENT OF ADVANCED TECHNOLOGIES

10 Saulėtekio, LT-10223 Vilnius
Tel. 236 6069
E-mail:

Head – Dr. Roland Tomašiūnas

DIVISION OF MATERIALS ENGINEERING

10 Saulėtekio, LT-10223 Vilnius
Tel. 236 6099
E-mail:

Head – Dr. Vytautas Grivickas

STAFF

Chief research fellow: Dr. R. Tomašiūnas.
Senior research fellow: Dr. V. Grivickas.
Research fellows: Dr. V. Bikbajevas Dr. T. Grinys (all part-time).
Junior research fellows: E. Jelmakas, I. Reklaitis, K. Gulbinas, M. Skapas (all part -time).
Doctoral students: E. Jelmakas, K. Gulbinas, I. Reklaitis, M. Skapas.
Post-doc: Dr. T. Malinauskas.
Senior engineer: G. Medeišienė (part-time).
Engineers: A. Arnatkevičiūtė, M. Dmukauskas, A. Balčytis (all part-time).
Technician: R. Beresnienė (part time).

RESEARCH INTERESTS

GaN technology
Optical nonlinearities of nano-structures (InGaAs, GaN)
Non-linear optical properties and mobility of organic molecules in polymers
Optical studies of carrier transport and recombination of silicon carbide and of layered semiconductors and their nanostructures

RESEARCH PROJECTS CARRIED OUT IN 2013

Projects Supported by University Budget

Development of Materials, Structures and Devices for Topical Semiconductor Optoelectronics . Prof. K. Jarašiūnas, Prof. S. Juršėnas, Dr. R. Tomašiūnas. 2011–2014.

GaN, InGaN, AlGaN multilayers and nanostructures were grown by MOCVD technology and investigated by microscopy (SEM), XRD, optical (spectroscopy, luminescence, non-linear optical methods) and electrical (mobility) techniques. Second and third order non-linear optical properties (II and III harmonic generation) of materials with noncentrosymmetry (dendrimers, phenylcarbazoles) were investigated. Layered TlGaSe2 and GaSe crystals and 6H-SiC structures were investigated by means of conventional and transient free-carrier absorption spectroscopy, photoacoustic deflection method.

Main publications:

Jelmakas, E., Tomašiūnas, R., Vengris, M., Rafailov, E., Krestnikov. I. 2013. Broadband absorption bleaching in chirped InGaAs quantum dot semiconductor optical amplifier operating at 1211-1285 nm. Optical materials. Amsterdam, Elsevier Science BV, vol. 35, iss. 12, 2171–2174.

National Research Projects

Research Council of Lithuania. Creation and Investigation of Azo Chromophore Functionalised GaN Surfaces (AZOGAN) (No. MIP-078/2012). Dr. R. Tomašiūnas. 2012–2014

Main goal of the project is to investigate new hybrid functional material – gallium nitride surface modified by azochromophore. The project expects to get and investigate a new effect – photostimulated optical orientation of azo chromophores influenced by gallium nitride surface. Vilnius university group in WP2 grew GaN on sapphire samples by metaloorganic chemical vapour deposition, which afterwards have been hydroxylated. A test to connect azochromophore to the hydroxylated GaN surface was performed. In parallel optical poling experiments performed on a related guest-host system of azophenylcarbazoles revealed a decreased relaxation rate and re-orientation capabilities for poled molecules.

Main publications:

Petruskevicius, R., Urbonas, D., Gabalis, M., Balcytis, A., Seniutinas, G., Tomasiunas, R., Getautis, V. 14th International Conference on Transparent Optical Networks, ICTON '13, June 23–27, 2013, Cartagena, Spain. IEEE Proc., p 4., ISBN: 978-1-4799-0683-3.

Seniutinas, G., Balčytis, A., Tomašiūnas, R., Petruškevičius, R., Getautis, V. 2013. Freezing out all-optical poling dynamics of azophenylcarbazole molecules in polycarbonate. Physical chemistry chemical physics, vol. 15, iss. 34, 14219–14228.

Lithuanian Government, Programme for cooperation research (JTP). Development and Industrial Application of New Generation of Materials Processing using Ultrafast Pulse Laser Sources. (VP1-3.1-ŠMM-10-V), partner resp. Dr. R.Tomašiūnas. In cooperation with Vilnius University Laser Centre. 2013–2015.

The main goal of the project is to develop high quality and high precision laser microfabrication technology using ultrafast pulsed lasers. One of the tasks the group was involved in concerned laser microfabrication of III-nitride structures to solve lift-off, light extraction issues for LED fabrication. Laser lithography was developed as a promising alternative to existing techniques and provided more flexibility in mesa formation for contact application.

European Community’s social foundation under Grant Agreement. Development and Characterization of Perspective Materials for Semiconductor and Nanotechnology by Cw and Ultrafast Spectrometry in a Wide Spectral Range (Lametech Mokslas) (VP1-3.1-ŠMM-08-K-01-004/KS-120000-1756), partner resp. Dr. T.Grinys. 2013–2015.

The main purpose of the project is to develop metal organic chemical vapor deposition (MOCVD) process of gallium nitride on silicon. The advantages over conventional sapphire substrate are reduced price and integration of gallium nitride into silicon technology. Instead of conventional aluminum nitride, the rear earth oxides as interlayer will be used to avoid the cracks of the film and chemical reaction between gallium nitride and silicon.

International Research Projects

FP7. Nanostructured Efficient White LEDs Based on Short-period Superlattices and Quantum Dots NEWLED. Dr. R.Tomašiūnas. 2012–2016.

The project will develop high efficiency and high brightness monolithic and hybrid all- semiconductor WHITE light-emitting GaN-based diodes. Power losses due to phosphor conversion and the problem of different ageing rates of the GaN LED pump will be eliminated by the development of phosphor free structures with increased brightness. The project will enhance the efficiency of yellow InGaAlP/AlGaAs LEDs by bandgap engineered superlattices. Novel light extraction approaches will target advanced directionality and colour adjustment. Advanced packaging will enable effective heat dissipation and light management.

Swedish Visby Program. Preparation and Characterization of Suspended Nanosheets of Layered Semiconductor Materials. Dr. V.Grivickas, Prof. J.Linnros, Dr. A.Fedotov. 2010–2013.

Optical absorption, defect investigation, photoacoustic responces in GaSe, InSe, TlGaSe2 and other layered semiconductors. Nanosheets membranes suspended on different substrates and structures.

Main publications:

Grivickas, V., Odrinskii, A., Bikbajevas, V., Gulbinas, K., 2013. Carrier trapping and recombination in TlGaSe2 layered crystals. Physica status solidi. B : Basic solid state physics, vol. 250, iss. 1, 160–168.

Nordic Energy Research Program. High Efficiency Integerated Solar Energy Converter HEISEC. Dr. T. Malinauskas. 2012–2014.

The main idea of the project is to combine photovoltaic and thermionic effects (PETE) into single high efficiency device; to demonstrate and verify the phenomenon of PETE and study the means to optimize material properties as well as to build a working demonstrator that can be utilized in further research and development. Ultimately the project aims at new solar energy converter technology demonstration including structure, materials and assessment.

MAIN R&D&I (RESEARCH, DEVELOPMENT AND INNOVATION) PARTNERS

Belarus State University (Belarus)
Royal Institute of Technology (Sweden)
Lawrence Livermore Nacional Laboratory (US)
University of Dundee (Scotland)
Center for Physical Sciences and Technology (Lithuania)
Kaunas University of Technology (Lithuania)

OTHER SCIENTIFIC ACTIVITIES

Dr. V. Grivickas –

Dr. R. Tomašiūnas –

  • member of the Technical Committee 73 Nanotechnologies of the Lithuanian Standards Board;
  • member of the Lithuanian Material Research Society.

Dr. V. Bikbajevas –

  • member of the Lithuanian Material Research Society.

DIVISION OF INFORMATION TECHNOLOGIES

29 M.K.Čiurlionio, LT-03100 Vilnius
Tel. 265 1797, fax 233 5648
E-mail:

Head – Dr. Arūnas Samuilis

STAFF

Senior research fellow: Dr. A.Samuilis (part time).
Research fellow: Dr. A.Konstantinov (part-time).
Senior engineers: V.Dadurkevičius, D.Ralys, F. Ralienė, J.Vaičiulis (all part-time).

RESEARCH INTERESTS

Artificial intelligence in various Lithuanian language computer implementations, e.g. machine translation, search systems, intelligent dictionaries
The development of the dictionary of contemporary Lithuanian

RESEARCH PROJECTS CARRIED OUT IN 2013

In 2013 the development of the English-Lithuanian-English and French-Lithuanian-French statistical machine translation systems was focused on achieving better translation quality by applying morphological analysis to publicly available bilingual corpora in order to refine them. The morphological analysis has been applied to both English and Lithuanian parts of the corpora. As a result, more precise translation pairs have been extracted from the corpora.

Projects Supported by University Budget:

Research of Possibilities to Use the Systemized Morphological Information of Lithuanian in the Search Systems. Dr. A.Samuilis. 2012–2014.

The possibilities to use the systemized morphological information of Lithuanian in the open source search systems have been examined in 2013. The open source search system platforms Lucene, zettair, sphinx and Xapian have been analyzed. The possibilities to Lithuanize the Lucene platform have been thoroughly examined.

DIVISION OF BIOMEDICAL TECHNOLOGIES

10 Saulėtekio, LT-10223 Vilnius
Tel. 236 6085
E-mail:

Head – Prof. Habil. Dr. Živilė Lukšienė

STAFF

Shief research fellow: Prof. Habil. Dr. Ž. Lukšienė.
Senior research fellow: Doc. Dr. A. Vaitkuvienė.
Research fellows: K. Aponienė, I. Buchovec.
Doctoral students: D. Varanius, V. Gėgžna.

RESEARCH INTERESTS

Application of light in life sciences
Biomedical optics: fundamental, applications, clinical investigation
Food safety and quality: development of novel non-thermal antimicrobial technologies
Biophotonic technologies for organic agriculture and food safety and quality: inactivation of pathogenic and harmful micro organisms
New materials in optical medicine, photodynamic therapy, photodiagnostics
Imaging and spectroscopy of bio-medical, biological objects: obstetrics, gynecology, reproduction, oncology, neurosurgery, immunology, biomaterials.

RESEARCH PROJECTS CARRIED OUT IN 2013

Projects Supported by University Budget

Optical Investigation of Biomedical Materials. Assoc. Prof. A.Vaitkuviene. 2012–2015.

Development of Modern Antimicrobial Technologies . Prof. Habil. Dr. Z. Luksiene. 2012–2016.

Two innovative approaches to control pathogenic and harmful microorganisms on different surfaces are in our focus: photosensitization and high power pulsed light. Obtained data indicate differential susceptibility of Gram(+) and Gram(-) bacteria to photosensitization. New experimental protocols are suggested to obtain effective and uniform inactivation of all pathogens.

Main publications:

Lukšienė, Ž., Buchovec, I., Kairytė, K., Paškevičiūtė, E., Viškelis, P., 2012. High-power pulsed light for microbial decontamination of some fruits and vegetables with different surfaces. Journal of Food, Agriculture and Environment, vol. 10, no. 3–4, 162–167.

Lukšienė, Ž., Buchovec, I., Viškelis, P., 2013. Impact of high-power pulsed light on microbial contamination, health promoting components and shelf life of strawberries. Food Technology and Biotechnology, vol. 51, no. 2, 284–292.

Lukšienė, Ž., Kokštaitė, R., Katauskis, P., Skakauskas, V., 2013. Novel approach to effective and uniform inactivation of gram-positive listeria monocytogenes and gram-negative salmonella enterica by photosensitization. Food Technology and Biotechnology, vol. 51, no. 3, 338–344.

National Research Projects

Research Council of Lithuania. IPTA 2013 World Laserology Congress www.ipta2013.com organization support. Assoc. Prof. A.Vaitkuviene. Overseas Congress Board members from international laser medicine societies travel, accomodation, congress venue were funded. Representatives of 14 countries presented their interdisciplinary scientific achievements in biomedical optics and laser medicine fields, 5 types of courses on laser safety and clinical application were provided for laser specialist, students, nurses and doctors.

Research Council of Lithuania. Innovative antimicrobial technologies for safety and quality of strawberries and raspberries . Prof. Habil. Dr. Z. Luksiene. 2012–2015.

According to FAOSTAT data, Lithuania is included in the list of the 20 best raspberry producers. Strawberry production and consumption is at the same level. Meanwhile, very fast metabolism of these perishable berries, low transportability and short shelf-life are main limiting factors to expand cultivation and plantation of these berries. Even Botrytis cinerea increases the postharvest losses to 15–50% and costs several billions dollars per year (Shtienberg, 2007). Due to the fact that postharvest fungicides are forbidden in EC, novel effective and ecologically friendly technologies to control microbial contamination of perishable berries are highly needed. Running this project new sistemic knowledge will be obtained on the possibility to control harmful and pathogenic microorganisms and to prolong shelf-life of perishable berries without any negative impact on their nutritional quality and organoleptic properties. Susceptibility of main food pathogens and harmful micromycetes to photoactivated chlorophyllin and ZnO in vitro are evaluated, paralelly investigating mechanism of action of theses agents.

Main publications:

Lukšienė, Ž., Brovko, L., 2013. Antibacterial photosensitization-based treatment for food safety. Food Engineering Reviews, vol. 5, no. 4, 185–199.

Kairytė, K., Kadys, A., Lukšienė, Ž., 2013. Antibacterial and antifungal activity of photoactivated ZnO nanoparticles in suspension. ournal of photochemistry and photobiology. B: Biology, vol. 128, 78–84.

Projects funded by Agency for Science, Innovation and Technology (MITA), (tool “Inočekiai LT”) (Assoc. Prof. Dr. A. Vaitkuviene).

a) Mutual project in the field of medical photo diagnostics The research on human invertebrate disc and liquid cervical smear samples autoflorescecnce with private company “Patologijos diagnostika” Ltd. (PD). Biosamples of cervical smear and vertebral disc spectroscopy method, spectra statistic evaluation modalities were investigated for at point of care applicable portable spectroscopy device creation

b) Mutual project in the field of laser device for biomedical spectroscopy investigation Laser 10STA-01-TH application for investigation of substrates suitability for biological sample investigation with private company ‘STANDA”. Differents substrates for a set of biomedical samples group were investigated for determination of substrates influence on sample spectra expression.

Main publications:

Varanius, D., Terbetas, G., Vaitkus, J. V., Vaitkuvienė, A., 2013. Spinal hernia tissue autofluorescence spectrum. Lasers in Medical Sscience, vol. 28, no 2, 423–430.

Kurtinaitis, J., Brazaitis, A., Porvaneckas, N., Gėgžna, V., Kvederas, G., 2013. Šlaunikaulio galvos kraujotaka po šlaunikaulio kaklo lūžio. Tūriniai dinaminio magnetinio rezonanso tomografijos tyrimo matavimai. Medicinos teorija ir praktika, vol. 19, nr. 1, 39–43.

Contractual Research

MTEP Project Analysis of Fluorescence Diagnosis Methods in Medicine. Assoc. Prof. A. Vaitkuviene. LASERCOM Ltd. signed an agreement for scientific collaboration and for funding of a scientific research: partially covered the costs of materials, bioethical license for biomedical research, and assigned salaries for researchers for 2012–2013.

Scientific literature search on spectral method application for usage at point of care was presented. Possible variants of original device construction were described on the basis of local and international advanced techniques availability. Collaboration scientific results were approved by company in 2013, future collaboration agreement under preparation.

MAIN R&D&I (RESEARCH, DEVELOPMENT AND INNOVATION) PARTNERS

Lund University, Medical Laser Centre (Sweden)
Uniform Service University of Health Science, Dept. Anatomy, Physiology and Genetics, Bethesda (USA)
Lithuanian companies: Integrated Optics, Standa, Lasercom, Patologijos Diagnostika.

OTHER SCIENTIFIC ACTIVITIES

Prof. Habil. Dr. Ž. Lukšienė –

  • member of management committee of COST FA1104 action;
  • Honorable adjunct professor of Queensland University (Austalia);
  • expert of Hong Kong Research Fund;
  • editorial board member of the Research and Reviews in BioSciences, Datasets international.

Assoc. Prof. A.Vaitkuvienė –

DEPARTMENT OF NEW MATERIALS RESEARCH AND MEASUREMENT TECHNOLOGY

Saulėtekio av. 9, bldg.III, LT-10222 Vilnius
Tel.: 236 6082, 268 7015, fax 236 6003
E-mail:

Head – Habil. Dr. Eugenijus Gaubas

STAFF

Chief research fellows: Habil. Dr. E. Gaubas, Prof. Habil. Dr. J. V. Vaitkus (part-time), Prof. Habil. Dr.V. Kažukauskas (part-time).
Senior research fellows: Dr. S. Tamošiūnas (part-time), Dr. J. Storasta (part time).
Research fellows: Dr. A. Mekys (part-time), Dr. R. Pūras, Dr. E. Žąsinas (part-time), Dr. T. Čeponis, Dr. V. Kalendra
Junior research fellows: J. Pavlov, A. Tekorius, V. Rumbauskas.
Doctoral students : A.Tekorius (since 2011), V. Rumbauskas (since 2011), J. Pavlov (since 2012).
Engineers: J.Kusakovskij, A.Velička, D.Bajarūnas, D.Meškauskaitė, A.Jasiūnas, V.Janonis, G. Mockevičius (all part-time).
Trainers: R. Bondzinskas, N.Vainorius, P. Cicėnas.

RESEARCH INTERESTS

Investigation of native and ionizing radiation induced defects and micro-inhomogeneities in semiconductors and structures
Carrier transport phenomena in organic materials and solar cell structures
Development of measurement technologies and instrumentation for the in situ characterization of material and device structures under heavy irradiations by hadrons
Development of measurement techniques for comprehensive characterization of photo-sensors, particle detectors and solar-cells

RESEARCH PROJECTS CARRIED OUT IN 2013

Projects Supported by University Budget

Investigation of Clusters in the Bulk and on the Surface in Semiconductors . Prof. Habil. Dr. J. V. Vaitkus. 2010–2014.

Project is implemented by investigation of magnetoresistance effect in Si structures and by analysis of temperature dependent the magnetoresistance mobility. The role of defect clusters is also unveiled by the comprehensive study of recombination characteristics within epitaxial and MCz Si structures. The wide range investigations of spectra of the thermal and photo- ionization of deep traps have been combined with DLTS and time-resolved photoluminescence spectroscopy in MOCVD GaN structures. Study of free carrier lifetime characteristics in MCz, Fz and Cz Si has been correlated with DLTS spectra in Si samples doped with covalent impurities of different density.

NATIONAL RESEARCH PROJECTS

Projects Supported by the Research Council of Lithuania

Research Council of Lithuania. (No. MIP-060/2013 ) In Situ and Ex Situ Evolution of Radiation Defects in Diamond and GaN Materials. Habil. Dr. E. Gaubas. 2013–2015.

The project is addressed to scientific and technological research by developing techniques for study of the radiation defects evolution during and after high energy irradiation in the wide band-gap materials.

Main publications:

Gaubas, E., Bajarūnas, D., Čeponis, T., Meškauskaitė, D., Pavlov, J., 2013. Optically induced current deep level spectroscopy of radiation defects in neutron irradiated Si PAD detectors. Lithuanian Journal of Physics / Lithuanian Physical Society, Lithuanian Academy of Science, vol. 53, No. 4, 215–218.

Operational Programme for Human Resources Development for 2001–2013 Strengthening Capacities of Researchersproject (No. VP1-3.1-SMM-07-K-03-010) Radiation Induced Nanoclusters in Si and GaN. Prof. Habil. Dr. J.V.Vaitkus. 2013–2015.

This research is addressed to analysis of the evolution and transformation of nanoclusters, radiation produced in crystalline Si and GaN structures.

Main publications:

Gaubas, E., Čeponis, T., Kalesinskas, V., 2013. Currents induced by injected charge in junction detectors. Sensors, vol. 13, iss. 9, 12295–12328.

Project Supported by the Lithuanian Agency of Science, Innovations and Technology

FP7 Project AIDA Advanced European Infrastructures for Detectors at Accelerators (No. 2013.09. 06 Nr.31V-70). Habil. Dr. E.Gaubas. 2013.

WP 8.3.2 of the FP7 AIDA project is addressed to the design, fabrication and testing of the improved instrument for radiation monitoring and comprehensive research of the irradiated materials, based on the measurements of carrier lifetime implemented by microwave response registration.

Projects Supported by the Lithuanian Academy of Science

Project (No. CERN-VU-02) Investigation of Radiation Defects in Si Structures and their Application for the Monitoring of Ionizing Radiation. Prof. Habil. Dr. J. V. Vaitkus, 2013.

Project is devoted to research of the magnetogalvanic effects and carrier transport characteristics in the irradiated Si structures.

INTERNATIONAL SCIENCE PROGRAMMES, PROJECTS AND CONTRACTS

Project Supported by the Lithuanian Agency of Science, Innovations and Technology FP7 Project AIDA “ADVANCED EUROPEAN INFRASTRUCTURES FOR DETECTORS AT ACCELERATORS” (No. 2013.09. 06 Nr.31V-70). Prof. Habil. Dr. J. V. Vaitkus. 2013 -2015.

VU WP Project is addressed to rapid dosimetry monitoring of the environment of accelerators.

Research project funded from the European Community’s Social Foundation Synthesis and Characterization of New Materials for Semiconductor- and Nano-Technologies by Means of Continuous and Ultrafast Spectroscopic Methods (Grant Agreement No. VP1-3.1-ŠMM-08-K-01-004/KS-120000-1756, the main project leader – Prof. Habil. Dr. V. Šablinskas). 2012–2014.

The project WP for the department (implemented by Habil. Dr. E.Gaubas and dr. T.Ceponis) is addressed to spectroscopy of wide-bandgap materials by advanced measurement techniques.

Main publications:

Gaubas E., Brytavskyi J., Čeponis T., Kusakovskij J., Tamulaitis G., 2013. Barrier capacitance characteristics of CdS-Cu2S junction structures. Thin solid films. Lausanne: Elsevier Science. Vol. 531, 131–136.

Gaubas, E., Borschak, V., Brytavskyi, I., Čeponis, T, Dobrovolskas, D., Juršėnas, S. A., Kusakovskij, J., Smyntyna, V., Tamulaitis, G., Tekorius, A., 2013. Nonradiative and radiative recombination in CdS polycrystalline structures. Advances in Condensed Matter Physics, vol. 2013, Art. no. 917543, 15 p.

Gaubas, E., Čeponis, T., Jasiūnas, A., Jelmakas, E., Juršėnas, S. A., Kadys, A., Malinauskas, T., Tekorius, A., Vitta, P., 2013. Study of carrier recombination transient characteristics in MOCVD grown GaN dependent on layer thickness. AIP advances, vol. 3, iss. 11. Art. No. 112128, 12 p.

CERN RD39 Collaboration program Cryogenic Tracking Detectors. Dr. J.Harkonen (Finland) and Dr. Zh. Li (USA). Vilnius group project Free Carrier Lifetime in Irradiated Si. Prof. Habil. Dr. J. V. Vaitkus, Habil.dr.E.Gaubas. 2002–2014.

Project is devoted to the study of the radiation hardness of Si material and device structures by microwave probed photoconductivity transients, pulsed capacitance and carrier drift induced current measurements.

CERN RD50 Collaboration program Radiation Hard Semiconductor Devices for Very High Luminosity Colliders. Dr. M. Moll. Contribution to the program Materials Characterization (Prof. M.Bruzzi) 2002–2014 and Defect Engineering (WODEAN project Prof.G.Lindstrom). Prof. Habil. Dr. J. V. Vaitkus. 2002–2011.

Analysis of radiation defect parameters by means of extrinsic photoconductivity spectra analysis, by lifetime dependence on the hadron irradiation fluences. Combined investigation of current, capacitance and photoconductivity transients in heavily irradiated material and detector structures.

Ordered Research Project

Presentation of the Model for Determination of the Atmospheric Refractive Index and Atmospheric Refractive Index Gradients Maps. Dr. S. Tamošiūnas. 2013.

Model is suitable for determination of the atmospheric refractive index over any locality of Lithuania. The maps of the stable atmosphere refractive index gradients based on multi-annual measurement data are provided for each month of the year.

MAIN R&D&I (RESEARCH, DEVELOPMENT AND INNOVATION) PARTNERS

Collaboration project according to a bilateral agreement Vilnius University and Centre of Physical and Technological Sciences, Lithuania. Habil. Dr.  E. Gaubas, 2012–2014. Development of radiation technologies.

National industry partners: ELMIKA, Ltd., Vilniaus Ventos Puslaidininkiai-VVP, Ltd., STANDA, Ltd (Lithuania). Development of device improvement technologies and techniques for technological control of materials

International cooperation partners: a net of partners is created by CERN RD39 and RD50 collaboration programmes those include more than 50 institutions in 19 countries.

OTHER SCIENTIFIC ACTIVITIES

Prof. Habil. Dr. J. V. Vaitkus –

  • chairman of the Division of Physics of the Lithuanian Academy of Sciences;
  • Fellow of the Institute of Physics (UK);
  • President of the Lithuanian Physical Society;
  • vice-chairman of CERN RD50 collaboration board,
  • member of CERN RD39 collaboration board;
  • deputy-editor of the Lithuanian Journal of Physics, and member of the international advisory board;
  • member of the Council of European Physical Society and general assembly of the IUPAP;
  • editorial board member of the journal Material Science (Medžiagotyra);
  • international advisory board member of the journal Physical Surface Engineering (Ukraine);
  • steering committee member of ROC-Lithuania-Latvia Foundation;
  • advisor to the Committee of Professional Qualification, European Physical Society;
  • member of the board of LITNET;
  • Co-president of the Lithuanian National Physics Conference, Vilnius, 2013.

Prof. Habil. Dr. V. Kažukauskas –

  • member of the project selection committee of Georgian Shota Rustaveli National Science Foundation (SRNSF);
  • President of Lithuanian DAAD Club (DAAD – German Academic Exchange Service).

Dr. S. Tamošiūnas –

  • director of the advanced scholars school Fizikos Olimpas.

DEPARTMENT OF SEMICONDUCTOR OPTOELECTRONICS

9 Saulėtekio, LT-10219 Vilnius
Tel. 236 6036, fax 236 6037
E-mail:

Head - Prof. Habil. Dr. Artūras Žukauskas

DIVISION OF OPTICAL DIAGNOSTICS

Head – Prof. Habil. Dr. Kęstutis Jarašiūnas,
E-mail:

DIVISION OF LUMINESCENCE

Head – Dr. Karolis Kazlauskas
E-mail:

DIVISION OF LIGHTING AND ELECTRONICS SYSTEMS

Head – Dr. Pranciškus Vitta
E-mail:

STAFF

Chief research fellows : Prof. Habil. Dr. K. Jarašiūnas, Prof. Habil. Dr. S. A. Juršėnas, Prof. Habil. Dr. G. Tamulaitis, Prof. Habil. Dr . E. Kuokštis (all part-time), Prof. Habil. Dr. A. Žukauskas.
Senior research fellows: Dr. R. Aleksiejūnas (part-time), Dr. K. Kazlauskas.
Research fellows: Dr. V. Gudelis (part-time), Dr. G. Liaugaudas, Dr. T. Malinauskas (on leave), Dr. S. Miasojedovas, Dr. J. Mickevicius (part-time), Dr. S. Nargelas (on leave), Dr. A. Novičkovas, Dr. P. Vitta (on-leave; part-time).
Junior research fellows: D. Dobrovolskas (part-time), A. Miasojedovas (part-time), S. Raišys (part-time), T. Serevičius (part-time), L. Skardžiūtė, (part-time), Dr. P. Ščajev, A. Tuzikas (part-time).
Senior engineer: L. Bastienė (part-time).
Engineer staff: J. Aleknavičius, P. Baronas, L. Dabašinskas, P. Eidikas, R. Komskis, O. Kravcov G. Kreiza, M. Mackoit, J. Trimailovas A. Vaitkevičius, (all part-time).
Doctoral students: D. Dobrovolskas, J. Jurkevičius, D. Ševčenko, D. Meškauskas, A. Petrulis, S. Raišys. L. Skardžiūtė, T. Serevičius, P. Ščajev, A. Tuzikas, A. Zabiliūtė.
Post-doc: S. Nargelas.

RESEARCH INTERESTS

Nonequilibrium carrier relaxation, transport and related photoelectrical phenomena in highly excited semiconductors and their nanostructures
Development of laser-based spectroscopic techniques with temporal, spectral, and spatial resolution for characterization of novel semiconductor materials for optoelectronics
Nondestructive characterization of wide band gap semiconductor materials
Optical nonlinearities in semiconductors
Development of organic optoelectronics materials and technologies
Photophysical properties of organic electronics materials
Formation of OLED structures and organic sensor systems
Characterization, optimization and applications of light-emitting diodes and their systems
Lighting systems with advanced colour rendition control for general and niche lighting
Lighting systems for vegetable growth with improved nutritional quality
Intelligent solid-state lighting systems for outdoor lighting

RESEARCH PROJECTS CARRIED OUT IN 2013

Projects Supported by University Budget

Development of Materials, Structures, and Devices for Semiconductor Optoelectronics . Prof. Habil. Dr. K. Jarašiūnas, Prof. Habil. Dr. S. A.Juršėnas, Dr. R. Tomašiūnas. 2011–2014.

Research facilities and techniques were customized for the characterization of GaN and diamond layers. Commentary optical techniques were applied for the study of carrier dynamics with variable temporal, spectral, and spatial resolution and analysis of materials parameters in wide excitation and density ranges.

Main publications:

Ščajev, P. Nargelas, S., Jarašiūnas, K., 2013. Time-resolved free carrier lifetime microscopy in bulk GaN. Phys. Status Solidi RRL, vol. 7, 647–650.

Ščajev, P. Gudelis, V. Tallaire, A. Barjon, J., Jarašiūnas, K., 2013. Injection and temperature dependent carrier recombination rate and diffusion length in freestanding CVD diamond. Phys. Status Solidi A 210, 2016–2021.

Characterization of Advanced Light-Emitting Diodes for Solid State Lighting and Measurement Technologies . Prof. Habil. Dr. A.Žukauskas. 2008–2013.

Negative differential photovoltage has been discovered in a double heterojunction of a light-emitting diode under modulated photoexcitation and high bias current. The effect was shown to to be due to the effect of photoconductivity on the series resistance of the heterojunction and due to the modulation of junction temperature.

Main publications:

Žukauskas, A., Meškauskas, D., Jakštas, V., Vitta, P., 2013. Negative differential photovoltage in a biased double heterojunction. Applied physics letters, vol. 102, iss. 7. Art. no. 073505 (3 p.).

National Research Projects

European Social Fund. Nonlinear Ex-Situ Optical Diagnostics and Optimization of Nitride Heterosctructures for Optoelectronics (OPTO) (Global Grant No. VP1-3.1-ŠMM-07-K-02-006). Prof. Habil. Dr. K.Jarašiūnas. 2012–2015.

Using the pico- and femtosecond spectroscopic techniques, diffently grown nitride layers and quantum well structures were investigated. These results provided insight that spectrally-resolved carrier generation-recombination rates as well diffusivity are excitation-dependent and would play a critical role in saturation of internal quantum efficiency in InGaN alloys.

Main publications:

Jarašiūnas, K., Nargelas, S., Aleksiejūnas, R., Miasojedovas, S., Vengris, M., Okur, S., Morkoç, H., Özgür, Ü., Giesen, C., Tuna, Ö., Heuken, M., 2013. Spectral distribution of excitation-dependent recombination rate in an In0.13Ga0.87N epilayer. Journal of Applied Physics, vol. 113, no. 10. Art. No. 103701 (9 p.).

Aleksiejūnas, R., Ščajev, P., Nargelas, S., Malinauskas, T., Kadys, A., Jarašiūnas, K., 2013. Impact of diffusivity to carrier recombination rate in nitride semiconductors: from bulk GaN to (In,Ga)N quantum wells. Japanese Journal of Applied Physics, vol 52. Art. No. 08JK01.

Nargelas, S., Jarašiūnas, K., Vengris, M., Sakalauskas, E., Yamaguchi, T., Nanishi, Y. 2013. Injection-activated defect-governed recombination rate in InN. Japanese Journal of Applied Physics, vol 52. Art. No. 08JD02.

European Social Fund. Control of the Photophysical Properties of Multifunctional Molecular Systems (Global Grant No. VP1-3.1-ŠMM-07-K-02-012). Prof. Habil. Dr. S.A.Juršėnas. 2012–2015.

The research provided physical insight on the control of multifunctional organic electronic material properties, increased the capabilities of Lithuanian scientists and technologists in the field of organic optoelectronics and opened the way for wider applications of Lithuania-made multifunctional materials.

Main publications:

Čekavičiūtė, M., Simokaitienė, J., Jankauskas, V., Raišys, S., Kazlauskas, K., Juršėnas, S.A., Gražulevičius, J.V., 2013. Structure-properties relationship of phenylethenyl-substituted triphenylamines. Journal of Physical Chemistry C: Nanomaterials, Interfaces and Hard Matter, vol. 117, no. 28, 7973–7980.

Gudeika, D., Reghu, R. R., Gražulevičius, J.V., Buika, G., Simokaitienė, J., Miasojedovas, A., Juršėnas, S.A., Jankauskas, V., 2013. Electron-transporting naphthalimide-substituted derivatives of fluorene. Dyes and Pigments, vol. 99, no. 3, 895–902.

European Social Fund. Improvement of Light Emission in III-nitrides by Boron Introduction to Increase Lattice Matching (Global grant No. VP1-3.1-ŠMM-07-K-02-014). Prof. Habil. Dr. G.Tamulaitis. 2012–2015.

The prevailing efficiency droop in AlGaN epilayers with strong carrier localization and high density of nonradiative recombination centres has been shown to be enhanced by nonradiative recombination due to carrier delocalization. Laser pulses with duration much shorter than the effective carrier lifetime were found to cause permanent photoluminescence quenching in AlGaN epilayers and structures at pulse energies about an order of magnitude lower than those causing the surface to melt.

Main publications:

Saxena, T., Tamulaitis, G., Shatalov, M., Yang, J., Gaska, R., Shur, M.S., 2013. Low threshold for optical damage in AlGaN epilayers and heterostructures. Journal of Applied Physics, vol. 114, no. 20. Art. No. 203103, 1–5.

European Social Fund. Novel Bifluorene Compounds with Flexible Structure for Optoelectronic Industry (BIFLUORENAS) (Grant No. VP1-3.1-ŠMM-10-V-02-023) Dr. K. Kazlauskas. 2013–2015.

The search for the novel bifluorene compounds bearing flexible backbone was initiated. Synthesis, functionalization, photophysical characterization of the intermediates of bifluorene compounds was started. The new compounds are expected to solve the reliability issue of a blue emitter, and also feature high fluorescence efficiency, high photostability, low threshold of amplified spontaneous emission and high carrier drift mobility.

Research Council of Lithuania. Mesopic Solid-state Light Sources (MesoLED) (No. ATE-01/2013). Prof. Habil. Dr. A. Žukauskas. 2012–2014.

The psychophysical properties (reaction time, contrast and color discrimination) of solid-state sources with a low correlated colour temperature (1700-2500 K; „firelight“), which can be used in many outdoor lighting applications have been investigated. “Firelight” phosphor converted LEDs with low circadian action have been proposed. A concept of a smart solid-state source of light with tuneable circadian action has been developed.

Research Council of Lithuania. Enhancement of Light Emission Efficiency in Wide-band-gap Nitride Semiconductors (LIUMIDI) (No. MIP-054/2012). Dr. J. Mickevičius. 2012–2014.

During the second year of the project, the investigations have been focused on: i) experimental studies of luminescence efficiency dependence on photoexcitation in AlGaN epilayers; ii) studies of relation between carrier dynamics and localization in high-Al-content AlGaN epilayers; iii) technological studies of AlGaN epilayer growth using VU MOCVD reactor; and iv) numerical studies of carrier generation, migration and recombination processes.

Main publications:

Mickevičius, J., Tamulaitis, G., Shur, M.S., Shatalov, M., Yang, J., Gaska, R., 2013. Correlation between carrier localization and efficiency droop in AlGaN epilayers. Applied Pphysics Letters, vol. 103, iss. 1, Art. No. 011906, 4 p.

Research Council of Lithuania. Plasmonic AlGaN/GaN Terahertz Emitters (MIP-064/2012). Dr. R. Aleksiejūnas. 2012–2014 (in cooperation with the Centre for Physical Sciences and Technology).

The growth of AlGaN/sapphire thick layers was optimized for VU MOCVD reactor. Carrier recombination and diffusion processes were then investigated in the optimized layers, which disclosed transport-driven nonradiative carrier recombination. Technology for the depositing of Schottky and ohmic contacts on AlGaN and GaN layers and production of Schottky diodes and HEMT transistors has been further developed.

Research Council of Lithuania. Conserving and Smart Lighting Technology for Art Display (TIMKAT) (No. MIP-098/2012). Dr. R. Vaicekauskas (Department of Computer Science, Vilnius University). 2012–2014.

A smart solid-state luminaire prototype was designed. The prototype is expected to be used as an efficient and conserving light source, which allows partial compensation of colours of aged artwork. The device has been demonstrated at the National M. K. Čiurlionis Art Museum. The subjective assessment of artwork under tuneable lighting has provided a quantitative basis for the engineering of solid state lighting sources with preferential colour rendition.

Main publications:

Liu, A., Tuzikas, A., Žukauskas, A., Vaicekauskas, R., Vitta, P. Shur, M.S., 2013. Cultural preferences to color quality of illumination of different artwork objects revealed by a color rendition engine. IEEE Photonics Journal, vol. 5, no. 4. Art. No. 6801010, 10 p.

Žukauskas, A., Vaicekauskas, R., Vitta, P., Zabiliūtė, A., Petrulis, A., Shur, M. S., 2013. Color rendition engineering of phosphor-converted light-emitting diodes. Optics express, vol. 21, no. 22, 26642–26656.

Žukauskas, A., Vaicekauskas, R., Tuzikas, A,. Vitta, P., Shur, M. S., 2013. Polychromatic solid-state light sources for the control of colour saturation of illuminated surfaces. Lithuanian Patent No. 5918.

Agency for Science, Innovation and Technology. Organic Optoelectronic Materials Targeted for Large Scale Synthesis (Org-LaScale) (No. 31V-28). Prof. Habil.Dr. S. A. Juršėnas. 2011–2013.

Over 50 novel anthracene, bianthracene, and carbazole materials with attractive optical and electrical properties for organic optoelectronics were synthesized. The derivatives were identified and characterized by means of thermal, microscopy, optical and electrical methods. Several pilot series of functionalized anthracene derivatives were supplied to the Mirae Interchem Co.Ltd. and JNC-Corp companies.

Main publications:

Serevičius, T., Adomėnas, P., Adomėnienė, O., Rimkus, R., Jankauskas, V, Gruodis, A., Kazlauskas, K., Juršėnas, S., 2013. Photophysical properties of 2-phenylanthracene and its conformationally-stabilized derivatives. Dyes and Pigments, vol. 98, no. 2, 304–315.

Juršėnas, S., Tumkevičius, S., Kazlauskas, K. , Jankauskas, V., Serevičius, T., Adomėnas, P., Rimkus, R., 2013. Nauji 1,5-dipakeisti 11-oksa-3-aza-3H-3-alkil- (arba aril-) dibenzo[a,m]indeno[2,1,7,6-ghij]pleiadenų dariniai, jų sintezė ir taikymas optoelektronikoje, Lithuanian Patent Application No. 2013 065 of 2013-06-27.

Agency for Science, Innovation and Technology. Optimization of Electrical, Optical and Thermal Characteristics of Solid-State Street Luminaire. (TERRALED) (No. 31V-30). Dr. P. Vitta. 2011–2013.

In cooperation with Terra Lucida Ltd, industrial prototypes of solid-state outdoor luminaire and smart programmable illumination controller were developed and introduced into the market. The 45W outdoor luminaire has optimized spectral, optical and thermal properties for reliable operation under outdoor conditions. The programmable controller was equipped with GPS sensor for the synchronization of the date and time settings in areas with unstable power supply.

Agency for Science, Innovation and Technology. National R&D commercialization program. Smart Solid-State Lighting with Tunable Colour Quality Parameters (SMARTLED) (31V-1). Dr. P. Vitta. 2012–2013.

An industrial prototype of tuneable solid-state luminaire for art and museum illumination has been developed and tested. The spin-off company Ledigma Ltd. has introduced this product into the market.

International Research Projects

7th Framework Programme. Marie Curie Initial Training Network Contract Training Network on Functional Interfaces for Silicon Carbide (NetFISiC) (No. PITN-GA-2010-264613). Prof. Habil. Dr. K. Jarašiūnas. 2011–2014.

In 2013, the studies were focused on sublimation grown bulk cubic SiC, determination of their fundamental properties as well as activation energies of residual defects, and investigation of their impact to carrier lifetime and mobility.

Main publications:

Ščajev, P., Jarašiūnas K., 2013. Temperature- and excitation-dependent carrier diffusivity and recombination rate in 4H-SiC. J. Phys. D: Appl. Phys, vol. 46, 265304, 1–6.

Ščajev, P., Karaliūnas, M., Kuokštis, E, Jarašiūnas, K., 2013. Radiative and nonradiative recombination rates in cubic SiC. J. Luminescence, vol. 134, 588–593.

7th Framework Programme. Coordination and Support Action. Accelerate SSL Innovation for Europe (SSL-erate) (No. 619249). Representative of Vilnius University Prof. Habil. Dr. A.Žukauskas. 2013–2016.

Started by the end of 2013, the Project aims at accelerating the uptake of high-quality solid-state lighting technology in Europe by means of open innovation with and by bringing

validated information to all relevant stakeholders.

Lithuanian Science Council and Taiwan Science Council. Programme of Mutual Funds for the Scientific Co-operation of the Republic of Lithuania and the Republic of Latvia with the Republic of China (Taiwan). One-Dimensional Nanostructures of Ternary Algan and Metal Doped-Zinc Oxide with Tunable Bandgaps: Growth, Characterization and Optical Properties. Prof. Habil. Dr. K Jarašiūnas. 2011–2013.

Polarity-dependent structural properties of MBE-grown ZnO layers on lattice-matched LiGaO2 substrate were combined with studies of optical and photoelectrical properties, using photoluminescence spectroscopy, time-resolved differential reflectivity, and light induced transient grating techniques. Impact of defects and grain boundaries on recombination and luminescence properties was studied in diamonds.

Main publications:

Ščajev, P., Trinkler, L., Berzina, B., Ivakin, E., Jarašiūnas, K., 2013. Influence of boron on donor–acceptor pair recombination in type IIa HPHT diamonds. Diamond and Relat. Mater, vol. 36, 35–43.

Ščajev, P., Nargelas, S., Jarašiūnas, K., Kisialiou, I., Ivakin, E., Deferme, W., Haen, J. D., Haenen, K., 2013. Crystallite size dependent carrier recombination rate and thermal diffusivity in undoped and boron doped CVD diamond layers. Phys. Status Solidi A, vol. 210, 2022–2027.

Research Council of Lithuania. Bilateral scientific collaboration program between Lithuania and Ukraine . II-VI Semiconductor Scintillators for X-ray Detectors (No. TAP LU 06/2012). Dr. J. Mickevičius. 2012–2013.

During the second year of the project, the studies were focused on the investigations of deep-level-related luminescence band mechanisms in a wide temperature range from 8 to 300 K. To relate recombination processes with the properties of scintillator detectors, the luminescence decay kinetics were studied. Additionally, numerical modeling of different recombination mechanisms was performed.

Main publications:

Shevchenko, D., Gavryushin, V., Mickevičius, J., Starzhinskiy, N., Zenya, I., Zhukov, A., Tamulaitis, G., 2013. Emission properties of ZnSe scintillation crystals co-doped by oxygen and aluminium. J. Luminescence, vol. 143, 473–478.

Contractual Research

Kaunas University of Technology. Investigation of Optical Properties of Dyes and Organic Multifunctional Molecules. Prof. Habil. Dr. S. A. Juršėnas. 2011–2013.

Sensor Electronic Technology Inc. (USA). Subcontract Agreement. Prof. Habil. dr. A. Žukauskas. 2013–2014.

Sensor Electronic Technology, Inc. (USA). Addendum to Cooperative Agreement. Prof. Habil. Dr. A. Žukauskas. 2008–2013.

Main publications:

Žukauskas, A., Vaicekauskas, R., Ivanauskas, F., Vaitkevičius, H., Shur, M. S., 2013. Multiwavelength solid-state lamps with an enhanced number of rendered colors. U.S. Patent No 8, 436, 526.

Energenas, Ltd. Investigation of Thermal, Electrical and Optical Parameters of Solid-State Light Sources. Dr. P.Vitta. 2013.

MAIN R&D&I (RESEARCH, DEVELOPMENT AND INNOVATION) PARTNERS

Kaunas University of Technology (Lithuania)
Centre for Physical Sciences and Technology (Lithuania)
Joint stock company Tikslioji sintezė (Lithuania)
Joint stock company Ledigma (Lithuania)
Rensselaer Polytechnic Institute, Troy NY (USA)
Virginia Commonwealth University, Richmond VA, (USA)
Institute of Photonics and Optoelectronics, National Taiwan University (R.O.C. Taiwan).

OTHER SCIENTIFIC ACTIVITIES

Prof. Habil. Dr. K. Jarašiūnas –

Prof. Habil. Dr. E. Kuokštis –

  • member of the Science Council of Lithuania (Committee of Natural and Technical Sciences), http://ww.lmt.lt.

Dr. P. Vitta –

  • Young-Researcher Scholarship of the Lithuanian Academy of Sciences.

Prof. Habil. Dr. A. Žukauskas –

LIQUID CRYSTALS LABORATORY

24 Naugarduko, LT-03225 Vilnius
Tel. 213 5553, fax 216 3417
E-mail:

Head – Assoc. Prof. Dr. Povilas Adomėnas

STAFF

Senior research fellows: Doc. Dr. P. Adomėnas, Dr. O. Adomėnienė.
Senior engineers: A. Gleiznys, A. Zakšauskas.
Engineers: O. Bobrovas, S. Jevstafiev, V. Kalcas, S. Bikantienė, A. Urbaitis, A. Voitechovičius, V. Žvinytė, R. Rimkus (part-time).
Technicians: M. Pikaikinas (part-time), A. Žvikas (part-time).

RESEARCH INTERESTS

New synthetic methods for nitrogen and sulphur heterocycles, poly-substituted anthracenes
New compounds and intermediates for OLED-technology
Efficient technologies for photovoltaic and OLED intermediates

MAIN R&D&I (RESEARCH, DEVELOPMENT AND INNOVATION) PARTNERS

JNC Corp. (Japan)
KISCO Ltd. (Japan)
Chukan Butsu Ltd. (Japan)
Cambridge Display Technology Ltd. (UK)
SYNTHON Chemicals GmbH & Co. KG (Germany)
Alfa Aesar Co. (UK)
Acros Organics B.V.B.A. (Belgium)
TCI Europe (Belgium)
Sumitomo Chemical Corp., Japan
Niche Materials Ltd. (UK).