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arXiv · 1509.03576

Coherence susceptibility as a probe of quantum phase transitions

Jin-Jun Chen·Jian Cui·Yu-Ran Zhang·Heng Fan
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Abstract

We introduce a coherence susceptibility method, based on the fact that it signals quantum fluctuations, for identifying quantum phase transitions, which are induced by quantum fluctuations. This method requires no prior knowledge of order parameter, and there is no need for careful considerations concerning the choice of a bipartition of the system. It can identify different types of quantum phase transition points exactly. At finite temperatures, where quantum criticality is influenced by thermal fluctuations, our method can pinpoint the temperature frame of quantum criticality, which perfectly coincides with recent experiments.

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Jin-Jun Chen, Jian Cui, Yu-Ran Zhang, Heng Fan. 2015-09-11. Coherence susceptibility as a probe of quantum phase transitions. https://doi.org/10.1103/physreva.94.022112

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