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arXiv · 2206.04422

Work statistics and thermal phase transitions

Ze-Zhou Zhang·Wei Wu
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Abstract

Many previous studies have demonstrated that work statistics can exhibit certain singular behaviors in the quantum critical regimes of many-body systems at zero or very low temperatures. However, as the temperature increases, it is commonly believed that such singularities will vanish. Contrary to this common recognition, we report a nonanalytic behavior of the averaged work done, which occurs at finite temperature, in the Dicke model as well as the Lipkin-Meshkov-Glick model subjected to the sudden quenches of their work parameters. It is revealed that work statistics can be viewed as a signature of the thermal phase transition when the quenched parameters are tuned across the critical line that separates two different thermal phases.

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Ze-Zhou Zhang, Wei Wu. 2022-06-09. Work statistics and thermal phase transitions. https://doi.org/10.1103/physreve.106.034104

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