Transverse spin polarization of a Rashba-Zeeman-coupled Fermi superfluid

Abstract

We apply the Bogoliubov-de Gennes theory to a superfluid Fermi gas that is confined to a disc, and analyze its transverse spin polarization that is produced by the simultaneous presence of an out-of-plane Zeeman field and an in-plane Rashba spin-orbit coupling. This is a finite-size effect whose physical origin is directly associated with the equilibrium mass-current density. Our numerical findings for the ground state suggest a bulk-boundary correspondence between characteristic features of the edge-bound transverse polarization and the changes in the momentum-space topology of the bulk.