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arXiv · 1905.12880

Dissipation Induced Nonstationarity in a Quantum Gas

Berislav Buca·Dieter Jaksch
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Abstract

Non-stationary long-time dynamics was recently observed in a driven two-component Bose-Einstein condensate coupled to an optical cavity [N. Dogra, et al. arXiv:1901.05974] and analyzed in mean-field theory. We solve the underlying model in the thermodynamic limit and show that this system is always dynamically unstable -- even when mean-field theory predicts stability. Instabilities always occur in higher-order correlation functions leading to squeezing and entanglement induced by cavity dissipation. The dynamics may be understood as the formation of a dissipative time crystal. We use perturbation theory for finite system sizes to confirm the non-stationary behaviour.

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Berislav Buca, Dieter Jaksch. 2019-12-31. Dissipation Induced Nonstationarity in a Quantum Gas. https://doi.org/10.1103/physrevlett.123.260401

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