Spin-Orbit Coupling Induced Coherent Production of Feshbach Molecules in a Degenerate Fermi Gas

TL;DR

This paper demonstrates that spin-orbit coupling can coherently produce Feshbach molecules in a degenerate Fermi gas and induce oscillations between molecules and polarized gas, revealing the role of SO coupling in pairing mechanisms.

Contribution

It provides experimental evidence that SO coupling enables coherent molecule formation and oscillations, highlighting its impact on pairing symmetry and potential topological superfluidity.

Findings

SO coupling induces coherent Feshbach molecule production

Oscillations observed between molecules and polarized gas due to SO coupling

Absence of phenomena in momentum-independent coupling case

Abstract

In this work we demonstrate a dynamic process in which SO coupling can coherently produce s-wave Feshbach molecules from a fully polarized Fermi gas, and can induce a coherent oscillation between Feshbach molecules and spin polarized gas. For comparison, we also show that such phenomena are absent if the inter-component coupling is momentum-independent. This demonstrates experimentally that SO coupling does provide finite matrix element between a singlet state and a triplet state, and therefore, implies the bound pairs of a system with SO coupling have triplet p-wave component, which can become topological superfluid by further cooling these pairs to condensation and confining them to lower dimension.