Quasiclassical theory of disordered Rashba superconductors

TL;DR

This paper develops a quasiclassical theoretical framework for two-dimensional Rashba superconductors with impurities, capturing the helical phase and spatial modulation of the order parameter induced by magnetic fields.

Contribution

It introduces a new set of quasiclassical equations and a generalized Ginzburg-Landau functional tailored for disordered Rashba superconductors with helical phases.

Findings

Derived equations describe helical phase in disordered Rashba superconductors.

Generalized Ginzburg-Landau functional includes linear gradient terms.

Framework facilitates studies of proximity effects in spin-orbit coupled systems.

Abstract

We derive the quasiclassical equations that describe two-dimensional superconductors with a large Rashba spin-orbit coupling and in the presence of impurities. These equations account for the helical phase induced by an in-plane magnetic field, with a superconducting order parameter that is spatially modulated along a direction perpendicular to the field. We also derive the generalized Ginzburg-Landau functional, which includes a linear-in-gradient term corresponding to the helical phase. This theory paves the way for studies of the proximity effect in two-dimensional electron gases with large spin-orbit coupling.