Spectral flow in vortex dynamics of d-wave superconductors

TL;DR

This paper investigates the spectral flow effects on flux flow conductivities in d-wave superconductors, revealing different vortex dynamics regimes and universal conductivities in certain limits.

Contribution

It introduces a detailed analysis of spectral flow contributions to flux flow conductivities across various vortex regimes in d-wave superconductors.

Findings

Spectral flow contribution matches s-superconductors in moderately clean limit.

Universal conductivity values in superclean regime at low magnetic fields.

Spectral flow contribution diminishes at higher fields in the superclean regime.

Abstract

We calculate Ohmic and Hall flux flow conductivities in the mixed state of d-wave superconductors taking into account the spectral flow along the anomalous branch of the states bound to vortex cores. Three regimes of vortex dynamics are found. In the moderately clean limit the contribution of the spectral flow to the conductivities coincides with that for s-superconductors. In the superclean regime in low magnetic fields both Ohmic and Hall conductivities acquire relaxation-time-independent universal values. The contribution of the spectral flow in the superclean regime is suppressed in higher fields. At not too low temperatures the contribution of the states above the gap is important.