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arXiv · 2310.00046

Dissipative Dicke time crystals: an atoms' point of view

Simon B. Jäger·Jan Mathis Giesen·Imke Schneider·Sebastian Eggert
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Abstract

We develop and study an atom-only description of the Dicke model with time-periodic couplings between atoms and a dissipative cavity mode. The cavity mode is eliminated giving rise to effective atom-atom interactions and dissipation. We use this effective description to analyze the dynamics of the atoms that undergo a transition to a dynamical superradiant phase with macroscopic coherences in the atomic medium and the light field. Using Floquet theory in combination with the atom-only description we provide a precise determination of the phase boundaries and of the dynamical response of the atoms. From this we can predict the existence of dissipative time crystals that show a subharmonic response with respect to the driving frequency. We show that the atom-only theory can describe the relaxation into such a dissipative time crystal and that the damping rate can be understood in terms of a cooling mechanism.

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Simon B. Jäger, Jan Mathis Giesen, Imke Schneider, Sebastian Eggert. 2023-09-29. Dissipative Dicke time crystals: an atoms' point of view. https://doi.org/10.1103/physreva.110.l010202

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