Papers by Author: S.G. Ovchinnikov

Abstract: The abnormal “normal” state and origin of high temperature superconductivity in cuprates are still not clear [1, 2]. The strong electron correlations (SEC) are known to be one of the main difficulties for the theory of high- cuprates. The conventional LDA (local density approximation) approach to the band structure fails in the regime of SEC. Various realistic multiband models of a layer at low energy result in the effective Hubbard or models [3 7]. The hybrid LDA+GTB scheme [8] generates the low-energy effective model with all parameters calculated ab initio.

Abstract: Determination of stable phases formed at the Fe/Si interface in (Fe/Si)n structure, grown by thermal evaporation in an ultrahigh vacuum system was performed using conversion electron Mössbauer spectroscopy (CEMS).

Abstract: Single crystals of cobalt oxyborates Co3O2BO3 and Co3-xFexO2BO3 were synthesized. The crystal structure and electric properties were investigated. The difference in the electrical resistivity behaviors was found. For parent Co3O2BO3 nor simple activation law, nor Mott variable range hopping (VRH) are acquirable to describe the experimental data in wide temperature region. In contrast for Co3-xFex O2BO3 Mott’s variable-range hopping conductivity clearly dominates.