Calculation and Measurement of the Electronic Part of the Thermal Conductivity of a Strong-Coupling Superconductor in Which Elastic Scattering of the Electrons Dominates

Abstract

We have generalized the theoretical expression for the electronic contribution $K_{\mathrm{es}}$ to the thermal conductivity in strong-coupling superconductors to include elastic scattering of the electrons. In the limit where the elastic scattering dominates, the resulting expression for $K_{\mathrm{es}}$ is equivalent to that of Bardeen, Rickayzen, and Tewordt except for a change in the energy-gap width; the renormalization function $Z_s$ does not explicitly appear. We have made measurements of the thermal conductivity of quench-condensed lead films which are in very good agreement with the theory, with no adjustable parameters.