Erratum: Directional Bistability and Nonreciprocal Lasing with Cold Atoms in a Ring Cavity [Phys. Rev. Lett. 121, 163603 (2018)].

This corrects the article DOI: 10.1103/PhysRevLett.121.163603.

Directional Bistability and Nonreciprocal Lasing with Cold Atoms in a Ring Cavity.

We demonstrate lasing into counterpropagating modes of a ring cavity using a gas of cold atoms as a gain medium. The laser operates under the usual conditions of magneto-optical trapping with no additional fields. We characterize the threshold behavior of the laser and measure the second-order optical coherence. The laser emission exhibits directional bistability, switching randomly between clockwise and counterclockwise modes, and a tunable nonreciprocity is observed as the atoms are displaced along the cavity axis.