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arXiv · 2403.15164

Symmetries & Correlations in Continous Time Crystals

Ankan Mukherjee·Yeshma Ibrahim·Michal Hajdušek·Sai Vinjanampathy
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Abstract

We demonstrate the inadequacy of mean-field theory by exploring the effects of initial state correlations on the dynamics of continuous time crystals, necessitating higher-order cumulant expansions. We exemplify this using cat states for which the mean field fails to predict a phase transition but the second order cumulant expansion theory captures it. Motivated by the symmetries of the system, we choose a truncation of cumulant theory at the second-order and demonstrate that it is sufficient to accurately capture the dynamical features overlooked by the mean-field.

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Ankan Mukherjee, Yeshma Ibrahim, Michal Hajdušek, Sai Vinjanampathy. 2024-03-22. Symmetries & Correlations in Continous Time Crystals. https://doi.org/10.1103/physreva.110.012220

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