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arXiv · 2011.12309

Multimode-polariton superradiance via Floquet engineering

Christian Høj Johansen·Johannes Lang·Andrea Morales·Alexander Baumgärtner·Tobias Donner·Francesco Piazza
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Abstract

We consider an ensemble of ultracold bosonic atoms within a near-planar cavity, driven by a far detuned laser whose phase is modulated at a frequency comparable to the transverse cavity mode spacing. We show that a strong, dispersive atom-photon coupling can be reached for many transverse cavity modes at once. The resulting Floquet polaritons involve a superposition of a set of cavity modes with a density excitation of the atomic cloud. The mutual interactions between these modes lead to distinct avoided crossings between the polaritons. Increasing the laser drive intensity, a low-lying multimode Floquet polariton softens and eventually becomes undamped, corresponding to the transition to a superradiant, self-organized phase. We demonstrate the stability of the stationary state for a broad range of parameters.

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Christian Høj Johansen, Johannes Lang, Andrea Morales, Alexander Baumgärtner, Tobias Donner, Francesco Piazza. 2020-11-24. Multimode-polariton superradiance via Floquet engineering. https://doi.org/10.21468/scipostphys.12.3.094

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