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arXiv · 0710.2581

Quantum criticality of the Lipkin-Meshkov-Glick Model in terms of fidelity susceptibility

Ho-Man Kwok·Wen-Qiang Ning·Shi-Jian Gu·Hai-Qing Lin
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Abstract

We study the critical properties of the Lipkin-Meshkov-Glick Model in terms of the fidelity susceptibility. By using the Holstein-Primakoff transformation, we obtain explicitly the critical exponent of the fidelity susceptibility around the second-order quantum phase transition point. Our results provide a rare analytical case for the fidelity susceptibility in describing the universality class in quantum critical behavior. The different critical exponents in two phases are non-trivial results, indicating the fidelity susceptibility is not always extensive.

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Ho-Man Kwok, Wen-Qiang Ning, Shi-Jian Gu, Hai-Qing Lin. 2008-07-03. Quantum criticality of the Lipkin-Meshkov-Glick Model in terms of fidelity susceptibility. https://doi.org/10.1103/physreve.78.032103

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