Flux flow in d-wave superconductors: Low temperature universality and scaling

We demonstrate that superclean d-wave superconductors with Δ2∞τ/EF≫1 display a novel type of vortex dynamics: At low temperatures, both dissipative and transverse components of the flux-flow conductivity are found to approach universal values even in the limit of infinite relaxation time. A finite dissipation in the superclean limit is explained in terms of the Landau damping on zero-frequency vortex modes which appear due to minigap nodes in the bound-state spectrum in the vortex core. In the moderately clean regime the scaling law at low T and low field is obtained.