Observation of chiral edge states with neutral fermions in synthetic Hall ribbons

TL;DR

This paper reports the experimental observation of chiral edge states in a synthetic Hall ribbon using ultracold neutral fermions, demonstrating key quantum Hall features in a controllable atomic system.

Contribution

It presents the first realization of fermionic chiral edge states in a synthetic gauge field setup with ultracold atoms, enabling new quantum Hall experiments.

Findings

Detection of edge states via site-resolved imaging

Observation of chiral edge state onset with bulk-edge coupling

Visualization of edge-cyclotron orbits during quench dynamics

Abstract

Chiral edge states are a hallmark of quantum Hall physics. In electronic systems, they appear as a macroscopic consequence of the cyclotron orbits induced by a magnetic field, which are naturally truncated at the physical boundary of the sample. Here we report on the experimental realization of chiral edge states in a ribbon geometry with an ultracold gas of neutral fermions subjected to an artificial gauge field. By imaging individual sites along a synthetic dimension, we detect the existence of the edge states, investigate the onset of chirality as a function of the bulk-edge coupling, and observe the edge-cyclotron orbits induced during a quench dynamics. The realization of fermionic chiral edge states is a fundamental achievement, which opens the door towards experiments including edge state interferometry and the study of non-Abelian anyons in atomic systems.