Comment on "Time Crystal in a Single-mode Nonlinear Cavity"

Carlos Navarrete-Benlloch

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arXiv · 2412.03585

Comment on "Time Crystal in a Single-mode Nonlinear Cavity"

Carlos Navarrete-Benlloch

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Abstract

I argue that a single driven quantum Van der Pol oscillator should not be considered a dissipative time crystal, contrary to previous claims. In particular, I show that its phase is prone to randomly drift when considering dephasing or additional nonlinearities, and hence its oscillations are not robust in that sense. The arguments I provide are applicable to many other models studied in the literature for which the limit of persistent oscillations coincides with the classical limit. I hope that this comment will spark a discussion about what should or should not be considered a time crystal (at least in the context of open quantum systems) and clarify it to a point.

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Carlos Navarrete-Benlloch. 2024-11-22. Comment on "Time Crystal in a Single-mode Nonlinear Cavity". https://arxiv.org/abs/2412.03585

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