Fermions take a curve in the extra-dimension


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.

M. ManciniĀ et al.,
Observation of chiral edge states with neutral fermions in synthetic Hall ribbons
Science 349, 1510 (2015)

See also the Science Perspective by A. Celi and L. Tarruell:

A. Celi and L. Tarruell
Probing the edge with cold atoms
Science 349, 1450 (2015)