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arXiv · 1902.05041

Detection of quantum phases via out-of-time-order correlators

Ceren B. Dağ·Kai Sun·L. -M. Duan
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Abstract

We elucidate the relation between out-of-time-order correlators (OTOCs) and quantum phase transitions via analytically studying the OTOC dynamics in a degenerate spectrum. Our method points to key ingredients to dynamically detect quantum phases via out-of-time-order correlators for a wide range of quantum phase transitions and explains the existing numerical results in the literature. We apply our method to a critical model, XXZ model that numerically confirms our predictions.

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Ceren B. Dağ, Kai Sun, L. -M. Duan. 2019-02-13. Detection of quantum phases via out-of-time-order correlators. https://doi.org/10.1103/physrevlett.123.140602

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