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arXiv · 1809.05427

Nonequilibrium polariton dynamics in a Bose-Einstein condensate coupled to an optical cavity

Gábor Kónya·Dávid Nagy·Gergely Szirmai·Peter Domokos
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Abstract

We study quasiparticle scattering effects on the dynamics of a homogeneous Bose-Einstein condensate of ultracold atoms coupled to a single mode of an optical cavity. The relevant excitations, which are polariton-like mixed excitations of photonic and atomic density-wave modes, are identified. All the first-order correlation functions are presented by means of the Keldysh Green's function technique. Beyond confirming the existence of the resonant enhancement of Beliaev damping, we find a very structured spectrum of fluctuations. There is a spectral hole burning at half of the recoil frequency reflecting the singularity of the Beliaev scattering process. The effects of the photon-loss dissipation channel and that of the Beliaev damping due to atom-atom collisions can be well separated. We show that the Beliaev process does not influence the properties of the self-organization criticality.

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Gábor Kónya, Dávid Nagy, Gergely Szirmai, Peter Domokos. 2018-11-16. Nonequilibrium polariton dynamics in a Bose-Einstein condensate coupled to an optical cavity. https://doi.org/10.1103/physreva.98.063608

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