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arXiv · 2311.13503

Non-Gaussian correlations in the steady-state of driven-dissipative clouds of two-level atoms

Giovanni Ferioli·Sara Pancaldi·Antoine Glicenstein·David Clement·Antoine Browaeys·Igor Ferrier-Barbut
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Abstract

We report experimental measurements of the second-order coherence function $g^{(2)}(\tau)$ of the light emitted by a laser-driven dense ensemble of $^{87}$Rb atoms. We observe a clear departure from the Siegert relation valid for Gaussian chaotic light. Measuring intensity and first-order coherence, we conclude that the violation is not due to the emergence of a coherent field. This indicates that the light obeys non-Gaussian statistics, stemming from non-Gaussian correlations in the atomic medium. More specifically, the steady-state of this driven-dissipative many-body system sustains high-order correlations in the absence of first-order coherence. These findings call for new theoretical and experimental explorations to uncover their origin and they open new perspectives for the realization of non-Gaussian states of light.

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Giovanni Ferioli, Sara Pancaldi, Antoine Glicenstein, David Clement, Antoine Browaeys, Igor Ferrier-Barbut. 2023-11-22. Non-Gaussian correlations in the steady-state of driven-dissipative clouds of two-level atoms. https://arxiv.org/abs/2311.13503

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