Fidelity susceptibility of the anisotropic $XY$ model: The exact solution

Qiang Luo; jize Zhao; Xiaoqun Wang

doi:10.1103/physreve.98.022106

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arXiv · 1805.05560

Fidelity susceptibility of the anisotropic $XY$ model: The exact solution

Qiang Luo·jize Zhao·Xiaoqun Wang

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Abstract

We derive several closed-form expressions for the fidelity susceptibility~(FS) of the anisotropic $XY$ model in the transverse field. The basic idea lies in a partial fraction expansion of the expression so that all the terms are related to a simple fraction or its derivative. The critical points of the model are reiterated by the FS, demonstrating its validity for characterizing the phase transitions. Moreover, the critical exponents $ν$ associated with the correlation length in both critical regions are successfully extracted by the standard finite-size scaling analysis.

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Qiang Luo, jize Zhao, Xiaoqun Wang. 2018-05-15. Fidelity susceptibility of the anisotropic $XY$ model: The exact solution. https://doi.org/10.1103/physreve.98.022106

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