Transport Properties in a Kondo Superconductor

Abstract

The transport coefficients in a Kondo superconductor have been calculated numerically in the framework of the Müller-Hartmann and Zittartz depairing theory. The calculations have been performed for the ultrasonic attenuation rate α_S and the thermal conductivity K_S. For certain typical values of T_K⁄T_c0, where T_K is the Kondo temperature and T_c0 is the superconducting transition temperature in the absence of magnetic impurities, the temperature variation of α_S and K_S shows very interesting behavior corresponding to the reentrance of superconductivity. Results are compared with the experimental data on the Zn–Mn system obtained by Lou and Bömmel for α_S and by Sánchez for K_S. Our calculations explain well the experimental data. They are also compared with the results based on the depairing theory by Abrikosov and Gor’kov and by Shiba.