The electron correlations in narrow energy bands are examined within the framework of the modi ed form of polar model. This model permits to analyze the effect of strong Coulomb correlation, inter-atomic exchange and ...

The evolution of electron quasistationary spectrum in open spherical quantum dot is under study within the effective mass and rectangular potential model. Within the framework of the S-matrix model the exact solution of ...

We derive an alternative representation for the f-electron spectral function of the Falicov-Kimball model from the original one proposed by Brandt and Urbanek. In the new representation, all calculations are restricted to ...

Within the framework of proton model with taking into account the piezoelectric interaction with the shear strain ε₆, a dynamic dielectric response of KD₂PO₄ type ferroelectrics is considered. Experimentally observed phenomena ...

Theoretical description of magnetic properties of antiferromagnetic state, induced by the longitudinal magnetic eld, in the Van Vleck singlet magnet with single-ion anisotropy of easy-plane type and ion spin S = ...

We calculate the intensity of spontaneous radiation of a system of non-linear quantum eld, where the nonlinearity is due to deformations of the Poison brackets of the generalized coordinates and momenta.

Statistical theory for ferroelectrics based on triple well anharmonic potential was used for the case of structural second order phase transition in Sn₂P₂S₆ crystals. Parameters of effective Hamiltonian of the model ...