Spin exchange-induced spin-orbit coupling in a superuid mixture

TL;DR

This paper explores how spin-exchange interactions in a dual-species Bose-Einstein condensate can induce spin-orbit coupling in the second species, revealing a complex phase diagram and offering new methods for creating SO coupling in quantum gases.

Contribution

It demonstrates that inter-species spin-exchange interactions can induce spin-orbit coupling in a second species, expanding the possibilities for SO coupling in superfluid mixtures.

Findings

Second species exhibits SO coupling via spin exchange

Rich phase diagram with novel phases

Potential to reduce heating issues in experiments

Abstract

We investigate the ground-state properties of a dual-species spin-1/2 Bose-Einstein condensate. One of the species is subjected to a pair of Raman laser beams that induces spin-orbit (SO) coupling, whereas the other species is not coupled to the Raman laser. In certain limits, analytical results can be obtained. It is clearly shown that, through the inter-species spin-exchange interaction, the second species also exhibits SO coupling. This mixture system displays a very rich phase diagram, with many of the phases not present in an SO coupled single-species condensate. Our work provides a new way of creating SO coupling in atomic quantum gases, and opens up a new avenue of research in SO coupled superfluid mixtures. From a practical point of view, the spin exchange-induced SO coupling may overcome the heating issue for certain atomic species when subjected to the Raman beams.