Microwave conductivity of a d-wave superconductor disordered by extended impurities: a real-space renormalization group approach

TL;DR

This paper employs a real-space renormalization group method to analyze microwave conductivity in a disordered d-wave superconductor, revealing how impurity-induced quasiparticle delocalization affects conductivity.

Contribution

It introduces a novel application of RSRG to compute microwave conductivity considering extended impurities in d-wave superconductors.

Findings

Delocalization of quasiparticles due to tunneling corrections.

Impurity effects significantly influence microwave conductivity.

RSRG captures localized and delocalized quasiparticle states.

Abstract

Using a real-space renormalization group (RSRG) technique, we compute the microwave conductivity of a d-wave superconductor disordered by extended impurities. To do this, we invoke a semiclassical approximation which naturally accesses the Andreev bound states localized near each impurity. Tunneling corrections (which are captured using the RSRG) lead to a delocalization of these quasiparticles and an associated contribution to the microwave conductivity.