Thermal conductivity and ultrasonic attenuation in heavy-fermion superconductors

We calculate the thermal conductivity and ultrasonic attenuation in anisotropic superconductors in which the scattering of quasiparticles by nonmagnetic impurities is the dominant process. The concentration of impurities is assumed to be low enough that broadening of quasiparticle states may be neglected, and hence the quasiparticle Boltzmann equation may be used. Detailed calculations are presented for two limiting choices of the normal-state phase shift, δN{}{π}/2 and δN={π}/2. The superconducting states considered are the axial and polar p-wave states and an axial d-wave state.