Current-carrying states in FFLO superconductors

TL;DR

This paper investigates the unique current-carrying behaviors of FFLO superconductors, revealing novel phenomena such as multiple critical currents, stable states, domain walls, and spontaneous supercurrents using a modified Ginzburg-Landau approach.

Contribution

It introduces a modified Ginzburg-Landau formalism to analyze equilibrium and nonequilibrium properties of FFLO superconductors, uncovering new current-carrying states and phenomena.

Findings

Existence of two different critical currents

Presence of two stable states for a given current

Spontaneous supercurrent in ring geometry

Abstract

We show that nonuniform superconductors of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) type conduct electric current in the way which is very different from the usual case. We discuss both equilibrium and nonequilibrium properties using a modified Ginzburg-Landau formalism. Among the novel features are the existence of two different critical currents and two distinct stable states able to carry a given current, the possibility of superconducting domain walls, and also a spontaneous supercurrent in a ring geometry.