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

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 نشر من قبل Shi-Jian Gu
 تاريخ النشر 2008
  مجال البحث فيزياء
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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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