Synthetic dimensions and spin-orbit coupling with an optical clock transition

TL;DR

This paper introduces a new method to create spin-orbit interactions in ultracold gases using an optical clock transition, enabling the study of topological states with synthetic dimensions.

Contribution

It demonstrates the synthesis of spin-orbit coupling via a single-photon clock transition and the creation of synthetic fermionic ladders with tunable magnetic flux.

Findings

Detection of spin-orbit coupling using clock spectroscopy

Measurement of chiral edge currents as a function of magnetic flux

Establishment of a platform for topological states in ultracold gases

Abstract

We demonstrate a novel way of synthesizing spin-orbit interactions in ultracold quantum gases, based on a single-photon optical clock transition coupling two long-lived electronic states of two-electron $^{173}$Yb atoms. By mapping the electronic states onto effective sites along a synthetic "electronic" dimension, we have engineered synthetic fermionic ladders with tunable magnetic fluxes. We have detected the spin-orbit coupling with fiber-link-enhanced clock spectroscopy and directly measured the emergence of chiral edge currents, probing them as a function of the magnetic field flux. These results open new directions for the investigation of topological states of matter with ultracold atomic gases.