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arXiv · 2310.05854

Time Crystal in a Single-mode Nonlinear Cavity

Yaohua Li·Chenyang Wang·Yuanjiang Tang·Yong-Chun Liu
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Abstract

Time crystal is a class of non-equilibrium phases with broken time-translational symmetry. Here we demonstrate the time crystal in a single-mode nonlinear cavity. The time crystal originates from the self-oscillation induced by a linear gain and is stabilized by a nonlinear damping. We show in the time crystal phase there are sharp dissipative gap closing and pure imaginary eigenvalues of the Liouvillian spectrum in the thermodynamic limit. Dynamically, we observe a metastable regime with the emergence of quantum oscillation, followed by a dissipative evolution with a time scale much smaller than the oscillating period. Moreover, we show there is a dissipative phase transition at the Hopf bifurcation of the model, which can be characterized by the photon number fluctuation in the steady state. These results pave a new promising way for further experiments and deepen our understanding of time crystals.

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Yaohua Li, Chenyang Wang, Yuanjiang Tang, Yong-Chun Liu. 2023-10-09. Time Crystal in a Single-mode Nonlinear Cavity. https://doi.org/10.1103/physrevlett.132.183803

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