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

36 research fellows (26 holding research degree).

 

RESEARCH AREAS

Investigation of Novel Organic and Inorganic Functional Materials and Structures

Development, Characterization, and Interdisciplinary Application of Advanced Electronic and Optoelectronic Devices 

DOCTORAL DISSERTATIONS MAINTAINED IN 2015 

K. Gulbinas. Photoelectrical and optical properties of indirect bandgap semiconductors TlGaSe2 and SiC.

T. Serevičius. Optimization of MOLECULAR emitters for new generation OLEDs.

L. Skardžiūtė. Tuning of the fluorescence properties of nitrogen heterocyclic compounds by polar substituents.

D. Ševčenko. Investigation of Defect-Related Luminescence of Isoelectronicaly Doped Zinc Selenide‑Based Scintillators.

A. Tekorius. Combined methods and instrumentation for dosimetric monitoring of the large fluence hadron irradiations.

 

DEPARTMENT OF ADVANCED TECHNOLOGIES

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

Head – Dr. Rolandas 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 fellows: Dr. V. Grivickas, Dr. A. Kadys, Dr. T. Malinauskas.
Research fellows: Dr. V. Bikbajevas, Dr. K. Gulbinas, Dr. T. Grinys (part-time).
Junior research fellows: I. Reklaitis, K. Gulbinas, M. Skapas (all part -time)
Doctoral students: K.Gulbinas, I. Reklaitis, M. Skapas.
Senior engineer: G. Medeišienė (part-time).
Technician: R. Beresnienė.

RESEARCH INTERESTS 

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

RESEARCH PROJECTS CARRIED OUT IN 2015 

Projects Supported by University Budget

Semiconductor Materials and Devices for Optoelectronics. Dr. R. Tomašiūnas. 2014–2015.

Growth of nitride multi quantum well structures by MOCVD technology has been continued. The structures have been investigated using microscopy (SEM), XRD, optical (spectroscopy, luminescence, non-linear optical methods) and electrical (mobility) techniques. FIB microfabricated voids in GaN overgrown have been investigated using SEM, Raman, AFM techniques providing insight into optimized void parameters for high quality GaN growth. Investigations on thallium based layered semiconductors have been continued. 

National Research Projects

Research Council of Lithuania. Development of Nonpolar Gan on Silicon Growth Technology with Rare-Oxide Interlayers (NEAPOLIS) (No. MIP-15283). Dr. T. Malinauskas. 2015–2017.

The non-polar, semi-polar crystalline GaN growth technology on silicon with rare-oxide interlayer is developed. Monocrystalline semi-polar truncated pyramids and polycrystalline GaN layers with dominating non-polar and semi-polar orientation were grown by MOCVD technique. The systematic analysis was performed on shape of the truncated pyramids in order to find out the growth rates in different directions. Research on growth rate is important for overgrowing the pyramids and forming the monocrystalline non-polar GaN layer.

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

Light extraction efficiency enhancement at flip-side surface of sapphire patterned by using femtosecond laser pulse irradiation was investigated. A new original method for LED chip separation and n-GaN layer exposure using femtosecond laser direct writing and 45◦ angle ablation geometry has been suggested and investigated. The LED devices prepared using this method have been investigated in function.

Main publications:

Jelmakas, E.,  Kadys, A., Malinauskas, T., Paipulas, D., Dobrovolskas, D., Dmukauskas, M., Selskis, A., Juodkazis, S., Tomašiūnas, R. 2015. A systematic study of light extraction efficiency enhancement depended on sapphire flipside surface patterning by femtosecond laser. J. Phys. D: Appl. Phys., vol. 48, 285104.

Reklaitis, I., Grinys, T., Tomašiūnas, R., Puodžiūnas, T., Mažulė, L., Sirutkaitis, V., Lin, C.H., Yang, C.C. 2015. A new geometrical approach for rapid LED processing by using femtosecond laser. Opt. Laser. Eng., vol. 74, 17.

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.

Concepts of integration of GaN into the on-silicon technology with Rare-oxide interlayer (such as gadolinium oxide, erbium oxide) were demonstrated. Erbium oxide showed crystallographic and thermal stability at metalorganic chemical vapor deposition (MOCVD) process conditions. Finally GaN was deposited on Bragg reflector structures consisting of Rare-oxide/silicon stacks. The X-ray diffraction and transmission electron microscopy analysis have revealed a deposited crystalline GaN of wurtzite structure with a smooth surface.

Main publication:

Grinys, T., Dargis, R., Kalpakovaitė, A., Stanionytė, S., Clark, A., Arkun, F.E., Reklaitis, I., Tomašiūnas, R. 2015. GaN growth on Si with rare-earth oxide distributed Bragg reflector structures. J. Cryst. Growth, vol. 424, 28.

International Research Projects 

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

The goal was to develop blue and green InGaN/GaN MQW for white light emitting diode (LED) devices. An extended study of charge carrier localization and delocalization in InGaN blue and green LED test structures was performed. Using frequency domain lifetime measurement technique charge carrier lifetimes in a broad range from millisecond to nanosecond scale were enabled to be extracted.

Main publication:

Kadys, A., Malinauskas, T., Grinys, T., Dmukauskas, M., Mickevičius, J., Aleknavičius, J., Tomašiūnas, R., Selskis, A., Kondrotas, R.,  Stanionytė, S., Lugauer, H., Strassburg, M. 2015. Growth of InN and In-rich InGaN layers on GaN templates by pulsed metalorganic chemical vapor deposition. J. Electron. Mater., vol. 44(1) 188.

Contractual Research

Scientific project Ultrafast Carrier Dynamics Measurements in 6H-Sic and Layered Semiconductors. Dr. V. Grivickas. 2013–2015.

Ultrafast optical absorption, transient grating and photoconductivity, two-photon investigation in semiinsulating SiC were performed.

Main publications:

Grivickas, P. Sampayan, S., Redeckas, K., Vengris, M., Grivickas, V. 2015. Probing of carrier recombination in n- and p-type 6H-SiC using ultrafast supercontinuum pulses. Mat. Sci. Forum, vol. 245, 821.

Suvanam, S.S., Gulbinas, K., Usman, M., Linnarson, M.K., Martin, D.M., Linnros, J., Grivickas, V., Hallén, A. 2015. 4H-SiC-Dielectric Interface recombination analysis using free carrier absorption. J. Appl. Phys., vol. 117, 105309.

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

Royal Institute of Technology (Sweden)
Lawrence Livermore Nacional Laboratory (USA)
Center for Physical Sciences and Technology (Lithuania)
Kaunas University of Technology (Lithuania)
Translucent Inc. (USA)
OSRAM Opto Semiconductors (Germany)
TOPGAN (Poland)

OTHER SCIENTIFIC ACTIVITIES 

Dr. V. Grivickas –

Dr. R. Tomašiūnas –

  • member of Vilnius University Doctoral Committee Materials Engineering (08T);
  • member of the Technical Committee 73 Nanotechnologies of the Lithuanian Standards Board;
  • member of the Lithuanian Material Research Society (LtMRS);
  • management committee member of the COST MP1403 action.

Dr. V. Bikbajevas –

  • member of the Lithuanian Material Research Society (LtMRS).

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, text parsing and data mining

The development of the dictionary of Contemporary Lithuanian

RESEARCH PROJECTS CARRIED OUT IN 2015

Development of 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. An open source stemming tool for Lithuanian has been built.

The Division participates in the buildup of the International Research Infrastructure - the Common Language Resources and Technology Infrastructure at the European Research Infrastructure Consortium (CLARIN ERIC).

Projects Supported by University Budget:

Research of Possibilities to Use the Systemized Morphological Information of Lithuanian in the Search Systems. Dr. A. Samuilis. 2012–2015.

The possibilities to use the systemized morphological information of Lithuanian in the open source search systems have been examined. 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

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

RESEARCH INTERESTS

Photonanotechnologies for control of pathogenic and harmful microorganisms in biomedicine and agro-food sector
Biomedical optics: fundamental, applications, clinical investigation
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 2015

Projects Supported by University Budget

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

Development of Modern Antimicrobial Technologies. Prof. Habil. Dr. Ž. Lukšienė. 2012–2016.

Two innovative approaches to control pathogenic and harmful microorganisms on different surfaces were focused on: 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:

Aponiene, K., Paskeviciute, E., Reklaitis, I., Luksiene, Z. 2015. Reduction of   microbial contamination of fruits and vegetables by hypericin-based photosensitization: Comparison with other emerging antimicrobial treatments. J. Food Engineer., vol. 144, 29.

Aponiene, K., Luksiene, Z. 2015. Effective combination of LED-based visible light, photosensitizer and photocatalyst to combat Gram (-) bacteria.J. Photochem. Photobiol., vol. 142, 257.

Rasiukeviciute, N., Bastienė, L., Valiuskaitė, A., Uselis, N., Viskelis, J. 2015. New nonchemical postharvest technologies reducing berry contamination. Zemdirbyste-Agriculture, vol. 4, 102.

National Research Projects

Research Council of Lithuania. Innovative Antimicrobial Technologies for Safety and Quality of Strawberries and Raspberries. Prof. Habil. Dr. Ž. Lukšienė. 2012–2015.

Running this project new systemic 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, in parallel investigating mechanism of action of theses agents.

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 –

  • management committee member of the COST FA1104 action;
  • honourable adjunct professor of Queensland University (Australia).

Assoc. Prof. Dr. A.Vaitkuvienė –

 

DEPARTMENT OF NEW MATERIALS RESEARCH AND MEASUREMENT TECHNOLOGY

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

Head – Prof. Habil. Dr. Eugenijus Gaubas

STAFF 

Chief research fellows: Prof. Habil. Dr. E. Gaubas, Prof. Habil. Dr. J. V. Vaitkus (part-time), Prof. Habil. Dr. V. Kažukauskas (part-time).
Senior research fellows: Assoc. Prof. Dr. S. Tamošiūnas (part-time), Assoc. Prof. Dr. J. Storasta (part-time), Dr. T. Čeponis.
Research fellows: Dr. A. Mekys (part-time), Dr. R. Pūras, Dr. E. Žąsinas (part-time).              Junior research fellows: J. Pavlov, A. Tekorius, V. Rumbauskas, D. Meškauskaitė.
Doctoral students: A. Tekorius (since 2011), V. Rumbauskas (since 2011), J. Pavlov (since 2012), D. Meškauskaitė (since 2014).
Engineers: A. Jasiūnas, G. Mockevičius (all part-time).
Trainees: D. Jotauta, K. Pūkas, V. Rymaš, L. Deveikis.

RESEARCH INTERESTS 

Investigation of native and ionizing radiation induced defects and micro-inhomogeneities in semiconductor materials and device 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
Spectroscopy of deep levels in wide-gap semiconductors as GaN and different technology diamond
Dosimetry of large fluence irradiations
Organic material (alanine) based dosimetry
Wide–gap material scintillators for detection and dosimetry of hadron irradiations 

RESEARCH PROJECTS CARRIED OUT IN 2015 

Projects Supported by University Budget

Investigation of Clusters in the Bulk and on the Surface in Semiconductors. Prof. Habil. Dr. J. V. Vaitkus. 2010–2015.

Project is implemented through investigation of magneto-resistance effect in Si structures and by analysis of temperature dependent magneto-resistance mobility. The role of radiation defect clusters is also considered by the comprehensive study of recombination characteristics within epitaxial and MCz Si structures. The wide range research of spectra of the thermal- and photo-ionization of traps has been implemented on in GaN and diamond structures by combining the pulsed photo-ionization, DLTS and time-resolved photoluminescence spectroscopy techniques. 

Development of Photo- and High Energy Radiation Detectors. Prof. Habil. Dr. E. Gaubas. 2014–2015.

Project is addressed at investigating detection regimes by combining the electrical and scintillation characteristics of wide–gap semiconducting materials such as GaN, CdS, ZnSe and synthetic diamond. Tentative detectors of various configurations have been designed and fabricated. The in situ and ex-situ variations of the radiation induced photo-ionization and time-resolved luminescence spectra have been examined. The profiling techniques for analysis of the current transients in junction and capacitor type detectors have been developed. Parameters of detectors, such as transit time, diffusion time and polarization recovery time have been extracted for sensors of various configurations.

Development of Techniques for Formation and Characterization of Cluster Defects in Wide-Gap Semiconductor Materials. Prof. Habil. Dr. E. Gaubas. 2014–2015.

Research of the formation and identification of cluster defects arranged through aggregation of large density of radiation induced vacancy and interstitial defects was carried out.  Formation of deep levels attributed to multi-vacancy structures in Si and GaN have been modelled. Tentative investigations of DLTS spectra with spectral peaks ascribed to radiation clusters have been performed. These results were correlated with pulsed photo-ionization spectra and with variations of the temperature dependent carrier trapping lifetime in the same materials and samples. The ESR spectra tentatively ascribed to clusters of radiation defects have also been examined in heavily irradiated Si.

National Research Projects 

Lithuanian Science Council (LSC) project: In Situ and Ex Situ Evolution of Radiation Defects in Diamond and Gan Materials (No. MIP-060/2013). Prof. Habil. Dr. E. Gaubas. 2013–2015.

The project is focused on 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 publication:

Gaubas, E., Ceponis, T., Meskauskaite, D., Kazuchits, N. 2015. Profiling of current transients in capacitor type diamond sensors. Sensors, vol. 15, 13424. 

European Social Fund Radiation Induced Nanoclusters in Si and Gan (Global grant No. VP1-3.1-SMM-07-K-03-010). Prof. Habil. Dr. J. V. Vaitkus. 2013–2015.

Research is addressed at analysing the evolution and transformation of nanoclusters, radiation produced in crystalline Si and GaN structures.

Main publications:

Gaubas, E., Ceponis, T., Kalesinskas, V., Pavlov, J., Vysniauskas, J. 2015. Simulations of operation dynamics of different type GaN particle sensors. Sensors, vol. 15, 5429.

Gaubas, E., Ceponis, T., Pavlov, J., Tekorius, A. 2015. In situ variations of the scintillation characteristics in GaN and CdS layers under irradiation by 1.6 MeV protons. Nucl. Instr. Meth. Phys. Res. B. 365, 159–162.

Gaubas, E., Ceponis, T., Pavlov, J. 2015. Modeling of radiation damage recovery in particle detectors based on GaN. Nucl. Instr. Meth. Phys. Res. B. 365, 163–167.

Cooperation programme in Science and Technology of Lithuania and Ukraine Project: Synthesis and Investigation of New Chalcogen and Halogen Materials for Micro-, Nano- and Optoelectronics (No. TAP-LU 02/2014). Prof. Habil. Dr. V. Kažukauskas. 2014–2015.

Main publications: 

V.V.Bozhko, A.V.Novosad, O.V.Parasyuk, N.Vainorius, V.Vertelis, A.Nekrošius, V.Kažukauskas. 2015. Photoconductivity relaxation processes in Cu1-xZnxInS2 solid solutions. Mat. Sci. Semicond. Proc., vol. 39, 665–670.

Bozhko, V. V., Novosad, О. V., Parasyuk, O. V., Kozer, V. R., Janonis, V., Sakavičius, A., Kažukauskas, V. 2015. Influence of cation-vacancy defects on the properties of CuInSe2–ZnIn2Se4 solid solutions. J. All. Comp., vol. 618, 712–717.

Bozhko, V.V., Novosad, A.V., Parasyuk, O.V., Khyzhun, N.Vainorius, O.Y., Nekrošius, A., Vertelis, V., Kažukauskas,V. 2015. Electrical properties and electronic structure of Cu1-xZnxInSe2 and Cu1-xZnxInS2 single crystals. J. Phys. Chem. Solids, vol. 82, 42–49.

European COST Action MP1307: Stable Next-Generation Photovoltaics: Unraveling Degradation Mechanisms of Organic Solar Cells by Complementary Characterization Techniques (Stablenextsol). Prof. Habil. Dr. V. Kažukauskas. 2014–2018.

Main publication:

Kažukauskas, V., Couderc, E., Sakavičius, A., Nekrošius, A., Vertelis, V., Reiss, P., Djurado, D., Faure-Vincent, J. 2015. Analysis of carrier transport in photovoltaic structures of P3HT with CdSe nanocrystals. Appl. Surf.  Sci., vol. 334, 169–173. 

Projects Supported by the Lithuanian Academy of Science

Project: Investigation of Radiation Defects in Si Structures and their Application for the Monitoring of Ionizing Radiation (No. MA- CERN-JV). Prof. Habil. Dr. J. V. Vaitkus. 2015.

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

Main publication:

Vaitkus, J.V., Rumbauskas, V., Mockevicius, G., Zasinas, E., Mekys, A. 2015. An evidence of strong electron–phonon interaction in the neutron irradiation induced defects in silicon. Nucl. Instr. Meth. Phys. Res. A.796, 114.

Project: Radiation Detectors (No. MA-CERN-EG). Prof. Habil. Dr. E. Gaubas. 2015.

Project is devoted to the research of various type radiation detectors.

International Science Programmes, Projects and Contracts

FP7 Project AIDA: Advanced European Infrastructures for Detectors at Accelerators. Prof. Habil. Dr. J. V. Vaitkus. 2013–2015.

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

Main publication:

Tekorius, A., Gaubas, E., Ceponis, T., Pavlov, J., Vaitkus, J., Glaser, M., Moll, M. 2014. Fluence and anneal dependent variations of recombination parameters in Si irradiated by 26 GeV protons. In Materials of 5th international conference Radiation Interaction with Materials: Fundamentals and Applications -2014. Technologija, Kaunas, 432–435.

H2020 Project AIDA-2: Advanced European Infrastructures for Detectors at Accelerators. Prof. Habil. Dr. J. V. Vaitkus, prof. Habil. Dr. G. Tamulaitis. 2015–2018.

VU WP (at the Department of New Materials Research and Measurement Technology) Project is devoted to search and investigations of the simple and cheap technology Si wafers for fabrication of dosimeters exploited in dose-reading using VUTEG-5-AIDA instrument.

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). Prof. Habil. Dr. V. Šablinskas). 2012–2014.

The project WP for the Department (implemented by Prof. Habil. Dr. E. Gaubas and Dr. T. Čeponis) is addressed at spectroscopy of wide-bandgap materials by advanced measurement techniques.

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, Prof. Habil. Dr. E. Gaubas. 2002–2015.

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 project: Materials Characterization (prof. M.Bruzzi) and Defect Engineering (WODEAN project). Prof. G. Lindstrom). 2002–2015.

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. 

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. Development of Radiation Technologies. Prof. habil. dr. E.Gaubas. 2012–2015.

National industry partners: ELMIKA, Ltd., Vilniaus Ventos Puslaidininkiai-VVP, Ltd , STANDA, Ltd (Lithuania). Prof. habil. dr. E.Gaubas.  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. Coordinator prof. habil. dr. J.V.Vaitkus.

Santa Cruz Institute for Particle Physics, University of California Santa Cruz, USA, prof. habil. dr. E.Gaubas. Research and development of the surface passivation technology for SLIM particle detectors. 

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.

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).  

Assoc. Prof. Dr. S. Tamošiūnas – 

  • director of the advanced scholars school Fizikos Olimpas.

 

DEPARTMENT OF SEMICONDUCTOR OPTOELECTRONICS

9 Saulėtekio, bldg III, LT-10222 Vilnius
Tel. 236 6032, fax 236 6059
E-mail:

Head - Dr. Karolis Kazlauskas 

DIVISION OF OPTICAL DIAGNOSTICS 

Head – Dr. Ramūnas Aleksiejūnas

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, Dr. K. Kazlauskas, Prof. Habil. Dr. E. Kuokštis (all part-time), Prof. Habil. Dr. A. Žukauskas.
Senior research fellows: Dr. R. Aleksiejūnas (part-time), Dr. T. Malinauskas, Dr. J. Mickevicius (part-time), Dr. P.Vitta.
Research fellows: Dr. D. Dobrovolskas (part-time), Dr. S. Miasojedovas, Dr. A. Miasojedovas, Dr. S. Nargelas, (part-time), Dr. A. Novičkovas (part-time), Dr. P. Ščajev (part-time), Dr. L. Skardžiūtė, Dr. T. Serevičius.
Junior research fellows: J. Jurkevičius, A. Petrulis, D. Ševčenko, D. Meškauskas.
Engineer staff: J. Aleknavičius, P. Baronas, L. Dabašinskas, P. Eidikas, S. Raišys, R. Komskis, G. Kreiza, A. Petrulis, J. Trimailovas, A. Vaitkevičius, A. Zabiliūtė-Karaliūnė, L. Bastienė.
Doctoral students: J. Jurkevičius, R. Komskis, G. Kreiza, D. Meškauskas, A. Petrulis, S. Raišys, D. Ševčenko, A. Zabiliūtė-Karaliūnė.
Post-docs: Dr. S. Nargelas.

RESEARCH INTERESTS 

Development of novel organic materials and technologies for optoelectronic applications
Photophysics of organic electronics compounds
Formation of OLED structures and organic sensor systems
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
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 2015 

Projects Supported by University Budget

Synthesis, Properties and Functional Structures of Organic Semiconductors. Prof. Habil. Dr. S. A. Juršėnas. 2014–2015.

New synthesis and purification routes of promising organic electronic compounds were developed. Design and functional properties of organic compounds were rationalized for specific application in optoelectronic devices such as OLEDs, sensors etc. New vacuum thermal evaporation as well as complex optical characterization facilities integrated in inert atmosphere gloveboxes were acquired.

Main publication:

Bucevicius, J., Skardziute, L, Dodonova, J., Kazlauskas, K., Bagdziunas, G., Jursenas, S., Tumkevicius, S. 2015. 2,4-Bis(4-aryl-1,2,3-triazol-1-yl)pyrrolo[2,3-d]pyrimidines: synthesis and tuning of optical properties by polar substituents. RSC Adv., vol. 5, 38610–38622.

Optoelectronics Technologies. Prof. Habil. Dr. A. Žukauskas. 2014–2015. 

New far-red phosphors for phosphor converted light-emitting diodes were investigated and characterised. Tunability of the circadian action of the tetrachromatic solid-state light sources was modelled and optimised numerically.

Main publications:

Zabiliute-Karaliune, A., Dapkus, H., Petrauskas, R.P., Butkute, S., Zukauskas, A., Kareiva, A. 2015. Cr3+ doped yttrium gallium garnet for phosphor-conversion light emitting diodes. Lith. J. Phys., vol. 55 (3), 200–207.

Butkute, S., Zabiliute, A., Skaudzius, R., Vitta, P., Beganskiene, A., Zukauskas, A., Kareiva, A. 2015. Sol-gel synthesis, characterization and study of substitution effects in different gallium-containing garnets. J. Sol-Gel Sci. Techn., vol. 76 (1), 210–219.

Zukauskas, A.,Vaicekauskas, R. 2015. Tunability of the circadian action of tetrachromatic solid-state light sources. Appl. Phys. Lett., vol. 106 (4), 041107.

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, InGaN/GaN quantum well structures and Al-rich AlGaN heterostructures of different technology were investigated. The study of carrier dynamics provided deeper information on carrier generation-recombination rates as well as diffusivity, their dependence on excitation and impact on saturation of internal quantum efficiency.   Set of LED-structures with varying doping, interlayer structure, growth regimes was grown to reach the optimized conditions for device-structure growth.

Main publication:

Aleksiejunas, R., Nomeika, K., Miasojedovas, S., Nargelas, S., Malinauskas, T., Jarasiunas, K., Tuna, O., Heuken, M. 2015. Carrier dynamics in blue and green emitting InGaN MQWs. Physica Status Solidi B 252, 977.

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.

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:

Skardziute, L., Dodonova, J., Voitechovicius, A., Jovaisaite, J., Voitechoviciute, A., Bucevicius, J., Kazlauskas, K., Jursenas, S., Tumkevicius, S. 2015. Synthesis and optical properties of the isomeric pyrimidine and carbazole derivatives: effects of polar substituents and linking topology. Dyes Pigm., vol. 118, 118–128.

Serevičius, T., Adomėnas, P., Adomėnienė, O.,  Karpavičius, K., Bucevičius, J., Komskis, R., Kreiza, G., Jankauskas, V., Kazlauskas, K., Juršėnas, S. 2015. Impact of non-symmetric 2,9,10-aryl substitution on charge transport and optical properties of anthracene derivatives. Dyes Pigm., vol. 122, 147–159.

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.

Luminescence efficiency improvement in III-nitrides was investigated using two approaches: i) technological studies of growth of boron-containing nitrides, such as BGaN and BAlGaN; and ii) studies of carrier dynamics in AlGaN and BGaN epilayers, and their heterostructures. BGaN epilayers with boron content up to 2.9%, 4.3% and 5.5% were grown on GaN/sapphire and AlN/sapphire templates, and 6H-SiC substrates, respectively, using MOCVD. Studies of carrier dynamics in AlGaN epilayers and quantum wells provided deeper insight on the carrier generation, redistribution and recombination processes in these materials, and their influence on the efficiency droop.

Main publications:

Malinauskas, T., Kadys, A., Stanionytė, S., Badokas, K., Mickevičius, J., Jurkevičius, J., Dobrovolskas, D., Tamulaitis, G. 2015. Growth of BGaN epitaxial layers using close coupled showerhead MOCVD.  Physica Status Solidi, vol. B 252, 1138.

Saxena, T., Shur, M., Nargelas, S., Podlipskas, Z., Aleksiejunas, R., Tamulaitis, G., Shatalov, M., Yang, J., Gaska, R. 2015. Dynamics of nonequilibrium carrier decay in AlGaN epitaxial layers with high aluminum content. Optics Express, vol. 23, 19646.

Saxena, T., Nargelas, S., Mickevičius, J., Kravcov, O., Tamulaitis, G., Shur, M., Shatalov, M., Yang, J., Gaska, R. 2015. Spectral dependence of carrier lifetime in high aluminum content AlGaN epitaxial layers. Journal of Applied Physics, vol. 118, 085705.

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.

Over 20 fluorene- and benzofluorene-cored oligomers were synthesized and investigated as potential lasing materials. The suitability of the compounds as lasing materials was assessed by quantifying concentration quenching of fluorescence quantum yield, by estimating pump thresholds of amplified spontaneous emission (ASE) as well as evaluating excited state lifetime and carrier drift mobility. Some of the compounds were shown to express very low thresholds of ASE (~300 W/cm2).

Main publications:

Kazlauskas, K., Kreiza, G., Radiunas, E., Adomėnas P., Adomėnienė, O., Karpavičius, K., Bucevičius, J., Jankauskas,V., Juršėnas, S. 2015. Concentration effects on spontaneous and amplified emission in benzo[c]fluorenes. Phys. Chem. Chem. Phys., vol. 17, 12935–12948.

Kazlauskas, K., Kreiza, G., Bobrovas, O., Adomėnienė, O., Adomėnas, P., Jankauskas, V., Juršėnas, S. 2015. Fluorene- and benzofluorene-cored oligomers as low threshold and high gain amplifying media. Appl. Phys. Lett., vol. 107, 043301.

Baronas, P., Kazlauskas, K., Kreiza, G., Jankauskas, V., Tomkeviciene, A., Simokaitiene, J., Grigalevicius, S., Grazulevicius, J.V., Jursenas, S. 2015. Differently linked fluorene-carbazole triads for light amplification. Dyes Pigm., vol. 123, 370–379.

Research Council of Lithuania. Distinction of the Influences of Defects and Carrier Localization on Emission in Green Ingan LED Structures (Delokingan) (No. MIP-079/2015). Dr. J. Mickevičius. 2015–2018.

The project is aimed at studying the impact of different type of defects and their aggregates on the emission properties of green LED structures, the connection between defects and material inhomogeneity, and the correlation between the defect type and density and technological growth conditions.

International Research Projects

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.

The preparation of the introductory map of green business opportunities for solid-state lighting (SSL) was contributed. The local industry and other green business stakeholders were contacted to discuss the SSL deployment in terms of sustainability and meaningfulness. The preparation of the introductory and situation analysis reports on lighting for health and well-being in Smart Cities was contributed. Presentation at a workshop for Lithuanian lighting designers to support raising awareness and implementation was given.

Research Council of Lithuania. Joint Lithuania-Japan Research Project. Towards Organic Laser Transistor (Laser-OTFT) (No. LJB-3/2015). Prof. Habil. Dr. S. A. Juršėnas. 2015–2017.

The project is aimed at the searching of new organic materials combining low stimulated emission threshold, excellent thin film forming properties, low concentration quenching, superior charge transport as well as low exciton quenching at high excitation densities for their implementation in organic laser working in transistor configuration. 

Contractual Research

Kaunas University of Technology. Investigation of Optical Properties of Dyes and Organic Multifunctional Molecules. Prof. Habil. Dr. S. A. Juršėnas. 2014–2015.

Kaunas University of Technology. New Structures of Organic Semiconductors for New Generation of Optoelectronic Devices. Prof. Habil. Dr. S. A. Juršėnas. 2014–2015. 

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

Aixtron AG (Germany)
Centre for Physical Sciences and Technology (Lithuania)
Durham University (United Kingdom).
Center of Organic Electronics and Photonics Research, Kyushu University (Japan)
Adolphe Merkle Institute, University of Fribourg (Switzerland)
University of Alicante (Spain)
JSC Tikslioji sintezė (Lithuania)
JSC Ledigma (Lithuania)
Kaunas University of Technology (Lithuania)
Rensselaer Polytechnic Institute, Troy NY (USA)
Sensor Electronic Technology Inc. (USA)
Taiwan National University
Veeco Inc. (USA)
Virginia Commonwealth University, Richmond VA (USA)

OTHER SCIENTIFIC ACTIVITIES

Prof. Habil. Dr. K. Jarašiūnas –

  • honourable member of Baltic-American Freedom Foundation Expert Committee.

Prof. Habil. Dr. E.Kuokštis –

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

Prof. Habil. Dr. A. Žukauskas –

  • editorial board member of the Journal of Solid State Lighting, http://www.journalofsolidstatelighting.com/.