High Tc Superconductors

An ab initio theoretical model is developed for High-Tc Superconductors starting with modified Coulomb potential energy function which is capable of incorporating short-range correlations between the two electrons forming Cooper pairs. we have embodied our modified model for the study of various superconducting properties of La2-xSrxCuO4 and related copper-oxide superconductor such as Coulomb repulsive parameter (¿*), Coupling strength (¿), transition temperature (Tc), the normalized specific heat jump (defined by the parameter R), relaxation time (¿ab) for electron-phonon interaction, resistivity (¿ab) and thermal conductivity. An attempt has been made to develop a formalism, which incorporates all possible excitons as exchange particles may be responsible for the formation of Cooper pairs. In this formalism the only free parameter is mass of exchange particle, which can be obtained by the band theory of solids.