Condensate formation in a dark state of a driven atom-cavity system

TL;DR

This paper reports the experimental and theoretical observation of condensate formation in a dark state within an ultracold atom-cavity system, revealing suppressed cavity coupling and unique symmetry properties of the condensate wave function.

Contribution

It introduces the first demonstration of dark state condensates in a driven atom-cavity system, combining experimental results with theoretical modeling to understand their properties.

Findings

Atoms in the dark state show suppressed cavity coupling.

The condensate wave function has anti-symmetric symmetry.

Dark state symmetry persists when pump is turned off.

Abstract

We demonstrate condensate formation in a dark state in an ultracold quantum gas coupled to a high-finesse cavity and pumped by a shaken optical lattice. We show experimentally and theoretically that the atoms in the dark state display a strong suppression of the coupling to the cavity. On the theory side, this is supported by solving the dynamics of a minimal three-level model and of the full atom-cavity system. The symmetry of the condensate wave function is anti-symmetric with respect to the potential minima of the pump lattice, and displays a staggered sign along the cavity direction. This symmetry decouples the dark state from the cavity, and is preserved when the pump intensity is switched off.