Dissociation of Feshbach molecules via spin-orbit coupling in ultracold Fermi gases

TL;DR

This paper demonstrates that spin-orbit coupling can induce dissociation of Feshbach molecules in ultracold Fermi gases, with experimental control over the process via Raman beam parameters, revealing new dissociation mechanisms.

Contribution

It introduces a novel method to dissociate Feshbach molecules using spin-orbit coupling in ultracold gases, experimentally realized with 40K atoms and Raman beams.

Findings

Dissociation rate is non-monotonic with Raman detuning.

Dissociation can be controlled by SO-coupling strength.

Experimental realization with 40K atoms confirms the theory.

Abstract

We study the dissociation of Feshbach molecules in ultracold Fermi gases with spin-orbit (SO) coupling. Since SO coupling can induce quantum transition between the Feshbach molecules and the fully polarized Fermi gas, the Feshbach molecules can be dissociated by the SO coupling. We experimentally realized this new type of dissociation in ultracold gases of 40K atoms with SO coupling created by Raman beams, and observed that the dissociation rate is highly non-monotonic on both the positive and negative Raman-detuning sides. Our results show that the dissociation of Feshbach molecules can be controlled by new degrees of freedoms, i.e., the SO-coupling intensity or the momenta of the Raman beams, as well as the detuning of the Raman beams.