The research of this scientific group is focused on the interactions between intense femtosecond laser pulses and various materials, the characterization of these materials and the development of new optical and terahertz frequency radiation sources using ultrafast spectroscopy and nonlinear optics techniques. The high power of available femtosecond laser pulses as well as the high laser-induced damage threshold in transparent isotropic and gaseous media enable us to accomplish our goals by exploring higher order nonlinear processes such as third-harmonic generation, four-wave and six-wave mixing, as well as four-wave parametric light generation and other nonlinear phenomena.

OTHzDSGNM gr labTerahertz group in the laboratory. Seated from the left: Dr. E. Gaižauskas, Dr. V. Pyragaitė, PhD stud. K. Steponkevičius; standing from the left: BSc stud. T. Kontrimas, MSc stud. E. Žeimys, Dr. V. Vaičaitis, and MSc stud. B. Makauskas


OTHzDSGNM erdvinis daznis

Spatial-frequency spectrum of conical light beam generated in sodium vapour

OTHzDSGNM 6bangis dazniu maisymasis

Six-wave mixing and third-harmonic generation in air


Group Members:

  • Habil. Dr. Virgilijus Vaičaitis,
  • Dr. Eugenijus Gaižauskas,
  • Dr. Viktorija Pyragaitė,
  • Dr. Vygandas Jarutis,
  • PhD student Kęstutis Steponkevičius,
  • MSc student Ernestas Žeimys,
  • BSc students Karolis Adomavičius and Tomas Kontrimas.

Main research topics:

  • Methods of ultrafast coherent laser spectroscopy;
  • Third-harmonic generation in air, metal vapour and other gases;
  • Four-wave and six-wave mixing in air, metal vapour and other gases;
  • Generation and detection of terahertz frequency radiation by the methods of nonlinear optics.

The research was performed in collaboration with Lithuanian and foreign science centers: University of Rochester (Rochester, USA), University of Maryland (Maryland, USA), University of Patras (Patras, Greece), University of Applied Sciences Jena (Jena, Germany), Scientific and Practical Materials Research Center (Minsk, Belarus), Institute of Semiconductor Physics (Vilnius, Lithuania). Group members have presented more than 100 presentations in international and local conferences and published more than 100 papers in national and international scientific journals and books.

Former Visitors and Alumni

Former Visitors:

  • Dr. Oleg Khasanov, Scientific-Practical Material Research Centre of the Belarus National Academy of Sciences, Belarus, 2014.
  • Dr. Olga Fedotova, Scientific-Practical Material Research Centre of the Belarus National Academy of Sciences, Belarus, 2014.
  • Simone Ost, Jena university of Applied Science, Germany, 2009.
  • Prof. Thomas Efthimiopoulos, University of Patras, Greece, 2007, 2008, 2011, 2012, 2013.
  • Dr. Dionysios Pentaris, University of Patras, Greece, 2007, 2008, 2010 2011, 2012, 2013.
  • Dr. Nikolaos Merlemis, Technical Educational Institute of Athens, Greece, 2008.

Alumni MSc:

  • Benas Makauskas, Broadband terahertz radiation generation by femtosecond laser pulses in air, 2015.
  • Artūras Belickas, Terahertz radiation generation by femtosecond laser pulses in air, 2012.
  • Mindaugas Arnašius, Numerical investigation of rectangular pulse envelope formation in amplifier chains, 2012.
  • Aurimas Savickas, Radiation from band gap solitons, 2009.
  • Mindaugas Kalinauskas, Multiphoton nonlinear processes in alkali metal vapour, 2008.
  • Jaroslav Smola, Anlysis of the femtosecond radiation induced refraction index changes in the bulk of transparent media, 2008.
  • Juozas Verseckas, Investigation of regenerative amplifier, 2007.
  • Tadas Lipinskas, Raman scattering in nonlinear KDP crystals, 2005.
  • Romanas Rus, Influence of pulsed laser radiation on the process of writing of interference gratings, 2001.