An Exotic Type of Fulde–Ferrel–Larkin–Ovchinnikov States in Spin-Orbit Coupled Condensates

We find for the first time 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, a novel type of Fulde–Ferrel–Larkin–Ovchinnikov ground state is rigorously revealed, in which the center-of-mass momentum of the fermion pair is proportional to the Zeeman field. We also generalize our exact analysis to the spin-orbit-coupled Bose–Einstein condensate.