Equilibrium states and thermodynamical properties of D-wave paired HTSC in the tight-binding model

摘要

A quasi two-dimensional d-wave paired superconductor in the BCS-type approach is considered. The tight-binding model corrections are taken into account by means of the conformal transformation defined in the framework of the formalism postulated recently by the authors. This method constitutes an extension of the van Hove scenario and exhibits a coincidence of the BCS-type and the Hubbard-type models, as well as makes possibility to determine equilibrium states of the system according to the symmetry rules. The results show essential changes in the critical temperature and specific heat jump for various forms of the dispersion relation. Additionally, a few examples of the energy gap contours obtained by the reverse conformal transformation are presented. [References: 30]