Description:statistical physics, Wigner crystals, mesoscopic systems
Abstract:The object of the research is the systems of limited number of correlated particles in a trap where strong interaction forces lead to the formation of the ordered structures (Wigner crystallization). Such crystallization is observed for electrons on the surface of liquid helium, cooled ions in various traps, cool dusty plasmas, vertices in superfluids and a stirred Bose-Einstein condensate, 2D quantum dots in semiconductor Coulomb blockades. The change of temperature or other external parameters determining the system conditions causes the erosion (melting) of the system structure or its reorganization (structural transition). However the macroscopic definitions of melting or other phase transitions are not stated unambiguously for the few-particle systems. The aims of the research are to develop the reliable and fast methods of obtaining the ground and metastable configurations, then to apply the methods for modeling of the structures forming under experimental conditions, and to describe the structural transitions using the statistical mechanics methods. The exploration of the systems is based on a statistical numerical (Monte Carlo) modeling. Various optimizing algorithms and their combinations are applied within the research seeking to give the system under investigation more freedom.
Monte Carlo simulation is implemented in C++ codes. Some codes use MPI libraries. Presently only non-MPI codes are executed on grid. Some additional libraries are used. Initial configurations of the systems under research are stored in separate files and are read when necessary within calculation cycle. Thus a folder containing all initial configuration files is needed for job to run. Statistical characteristics of the system under research are evaluated after 10^9 Monte Carlo cycles. However more cycles might be necessary for some complex systems. The systems under research can vary by the number of particles, types of particles and so on. Statistical characteristics of those need to be evalua