Fluctuation conductivity in disordered superconducting films

TL;DR

This paper investigates how superconducting fluctuations influence both longitudinal and Hall conductivities in disordered films, providing analytic expressions across the entire phase diagram by connecting phenomenological and microscopic approaches.

Contribution

It introduces a novel analytic method based on the Usadel equation to calculate fluctuation corrections in disordered superconducting films across all relevant conditions.

Findings

Derived compact formulas for fluctuation corrections

Unified classical and quantum fluctuation effects

Applicable across the entire phase diagram

Abstract

We study the effect of superconducting fluctuations on the longitudinal and the transverse (Hall) conductivity in homogeneously disordered films. Our calculation is based on the Usadel equation in the real-time formulation. We adjust this approach to derive analytic expressions for the fluctuation corrections in the entire metallic part of the temperature-magnetic field phase diagram, including the effects of both classical and quantum fluctuations. This method allows us to obtain fluctuation corrections in a compact and effective way, establishing a direct connection between phenomenological and microscopic calculations.