Quasiparticle conductivities in disordered d-wave superconductors.
We study the quasiparticle transport coefficients in disordered d-wave superconductors. We find that spin and charge excitations are generally localized unless magnetic impurities are present. If the system is close to a nesting point in the impurity-scattering unitary limit, the tendency towards localization is reduced while the quasiparticle density of states gets enhanced by disorder. We also show that the residual repulsive interaction among quasiparticles has a delocalizing effect and increases the density of states.
Fabrizio
Michele
M
Istituto Nazionale di Fisica della Materia and International School for Advanced Studies (SISSA), Via Beirut 2-4, I-34014 Trieste, Italy.
Dell'Anna
Luca
L
Castellani
Claudio
C