Thermal Conductivity Due to Impurity Scattering for Superconductors with Overlapping Bands

Abstract

Calculations of thermal conductivity due to impurity scattering for BCS-type superconductors carried out by Bardeen, Rickayzen, and Tewordt (BRT) are extended to the case of the two-spherical-band model proposed by Suhl, Mathias, and Walker using some of the results obtained recently by Sung and Shen concerning the specific heat of such superconductors. The curve obtained for the ratio of thermal conductivities in the superconducting and the normal state which is valid near the transition temperature yields values lower than the corresponding results obtained by BRT. This is caused by the lowering of the mean free path of the excitations occasioned by the possibility of intraband scattering.