Unconventional Fulde-Ferrel-Larkin-Ovchinnikov states in spin-orbit coupled condensates: exact results

TL;DR

This paper presents an exact solution for a model of s-wave superconductors with spin-orbit coupling and Zeeman field, revealing a novel FFLO state with momentum proportional to the Zeeman field and discussing effects on spin-orbit Bose-Einstein condensates.

Contribution

It provides the first exact solution demonstrating an unconventional FFLO state in spin-orbit coupled superconductors and explores related condensate dynamics.

Findings

Exact solvability of the model Hamiltonian.

Discovery of a new FFLO ground state with momentum linked to Zeeman field.

Analysis of Zeeman field effects on spin-orbit Bose-Einstein condensates.

Abstract

We find that a model Hamiltonian of s-wave superconductors in the presence of spin-orbit interactions and a Zeeman field is exactly solvable. Most intriguingly, based on the exact solutions, an unconventional type of Fulde-Ferrel-Larkin-Ovchinnikov (FFLO) ground state is rigorously revealed, in which the center-of-mass momentum of the fermion pair is proportional to the Zeeman field. We also elaborate on the drifting effect of the Zeeman field on the spin-orbit-coupled Bose-Einstein condensate.