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arXiv · 2405.09885

Symmetry breaking and non-ergodicity in a driven-dissipative ensemble of multi-level atoms in a cavity

Enrique Hernandez·Elmer Suarez·Igor Lesanovsky·Beatriz Olmos·Philippe W. Courteille·Sebastian Slama
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Abstract

Dissipative light-matter systems can display emergent collective behavior. Here, we report a $\mathbb{Z}_2$-symmetry-breaking phase transition in a system of multi-level $^{87}$Rb atoms strongly coupled to a weakly driven two-mode optical cavity. In the symmetry-broken phase, non-ergodic dynamics manifests in the emergence of multiple stationary states with disjoint basins of attraction. This feature enables the amplification of a small atomic population imbalance into a characteristic macroscopic cavity transmission signal. Our experiment does not only showcase strongly dissipative atom-cavity systems as platforms for probing non-trivial collective many-body phenomena, but also highlights their potential for hosting technological applications in the context of sensing, density classification, and pattern retrieval dynamics within associative memories.

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Enrique Hernandez, Elmer Suarez, Igor Lesanovsky, Beatriz Olmos, Philippe W. Courteille, Sebastian Slama. 2024-05-16. Symmetry breaking and non-ergodicity in a driven-dissipative ensemble of multi-level atoms in a cavity. https://arxiv.org/abs/2405.09885

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