Josephson Effect in Fulde-Ferrell-Larkin-Ovchinnikov Superconductors

TL;DR

This paper demonstrates that applying a magnetic field can recover the suppressed Josephson current in junctions involving FFLO superconductors, providing a method to detect and analyze the FFLO state.

Contribution

It reveals how magnetic fields can restore Josephson current in FFLO superconductor junctions, enabling detection and characterization of the FFLO state.

Findings

Magnetic field can recover Josephson current in FFLO superconductor junctions.

The recovery depends on the field's strength and direction.

Josephson effect can be used to detect and measure the FFLO order parameter.

Abstract

Due to the difference in the momenta of the superconducting order parameters, the Josephson current in a Josephson junction between a Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) superconductor and a conventional BCS superconductor is suppressed. We show that the Josephson current may be recovered by applying a magnetic field in the junction. The field strength and direction at which the supercurrent recovery occurs depend upon the momentum and structure of the order parameter in the FFLO state. Thus the Josephson effect provides an unambiguous way to detect the existence of an FFLO state, and to measure the momentum of the order parameter.