Fyzikální ústav Akademie věd ČR

Theory of random systems, in particular spin glasses, is pursued. Microscopic approaches bases on the real-replica method combined with Thouless-Anderson-Palmer equations are used to understand the mean-field theory of Ising and other spin glass models. Genesis of the full solution with a continuous replica-symmetry breaking is pursued in the asymptotic region below the transition to the glassy phase.  The full text >>

Electron correlations are studied in tight-binding models with a screened local interaction of the Hubbard type. Advanced summation methods of Feynman diagrams for two-particle Green functions are the core of our interest. Various simplified forms of parquet equations mixing self-consistently multiple electron-electron and electron-hole scatterings are used to describe peculiarities of the strong-coupling regime.   The full text >>

Structural properties and mechanisms of formation of surface nanostructure on metal as well as semiconductor substrates are investigated by numerical simulations. The objective is to explain formation of nanostructures on the microscopic level and by this provide interpretation of resent experiments. Molecular dynamics and Monte-Carlo simulations are combined with approximative analytical methods to achieve description of relevant statistical mechanical quantities during growth by molecular beam epitaxy or by pulsed laser   The full text >>

This research concentrates on the electron response to sudden/fast changes of boundary conditions, like coupling to the particle reservoirs (leads) and to the environment (thermal baths), or to the excitation by short external pulses of light or other fields. The research aims at an adequate description of the non-equilibrium correlated state during the initial transient, the decay of correlations as a gate to the non-equilibrium kinetic stage of evolution and to the final equilibration.   The full text >>