Head of department prof., dr. Vladas Vansevičius
Main goals of the department:
1. Theoretical investigations and modelling of chaotic systems, neural networks, and nanostructures.
2. Theoretical and experimental investigations of fluctuations, hot electron and phonon dynamics.
3. Theoretical and observational investigations of complex megasystems.
Research directions of the department:
1. Complex neural networks and desynchronization algorithms.
2. Chaos control algorithms.
3. Classical and quantum electron systems.
4. Terahertz radiation sources.
5. Fluctuations and dynamics of coupled electron-phonon systems.
6. Plasmons in dynamics of highly excited electrons and phonons.
7. Spectrophotometry of megasystems.
8. Chemodynamical evolution of complex megasystems.
Nonlinear Dynamics and Nanophysics Laboratory
The analysis of nonlinear dynamics, quantum and kinetic problems are performed by means of various approximate analytical (a method of separation of fast and slow motions, averaging method, phase reduction method, etc.) as well as numerical (algorithms of numerical integration of differential equations, Monte Carlo method, etc.) methods
Fluctuation research laboratory
|Nanosecond gated microwave X-band/Ka band modulation-type radiometric setup for measurement of hot-electron fluctuations at microwave frequencies. On-wafer measurements at room temperature are conducted using coaxial probe station. Waveguide probing can be used instead at a liquid nitrogen temperature. Fluctuations are measured only during the short pulse and that enables the research of kinetic processes in semiconductors. Voltage pulse duration ranges from 10 nanoseconds to 15 microseconds. Electric fields can exceed 100 kV/cm. Joule heating becomes unimportant because of short pulses.|
|Capacitance-voltage (50 kilohertz – 30 megahertz) and voltage-current measurement system available. It can be used for electron gas profile estimation in the 2DEG transistor channels as well as finding of 2DEG density.|
|Agilent–Süss–Maury spectrometer for transistor on wafer measurements of microwave response and noise spectra and microwave power at frequencies from 0.1 to 50 GHz. The main direction – SiGe heterobipolar transistors and GaN heterostructure field effect transistors.|
|Nanosecond voltage-pulse setup (pulse duration 0.2...100 ns) is used for hot-electron drift velocity measurements in electric field range up to 300 kV/cm. Channel self-heating effects are minimized.|
|Electro-magnet (2 Tesla)|
Monte Carlo and other codes are available for numerical simulation of hot-electron fluctuations in semiconductor heterostructures and transistors.
2. Research Council of Lithuania, the project “Star Formation in Galaxy Disks: Global vs. Local“, project leader dr. D. Narbutis (2015–2018).
The project aims to determine spatial and dynamical parameters of ongoing star formation in the galaxy NGC598 disk by coordinated use of observational data obtained with ground- and space-based telescopes.