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arXiv · 2111.10768

Fidelity-mediated analysis of the transverse-field $XY$ chain with the long-range interactions: Anisotropy-driven multi-criticality

Yoshihiro Nishiyama
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Abstract

The transverse-field $XY$ chain with the long-range interactions was investigated by means of the exact-diagonalization method. The algebraic decay rate $\sigma$ of the long-range interaction is related to the effective dimensionality $D(\sigma)$, which governs the criticality of the transverse-field-driven phase transition at $H=H_c$. According to the large-$N$ analysis, the phase boundary $H_c(\eta)$ exhibits a reentrant behavior within $2 2$.

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Yoshihiro Nishiyama. 2021-11-21. Fidelity-mediated analysis of the transverse-field $XY$ chain with the long-range interactions: Anisotropy-driven multi-criticality. https://doi.org/10.1140/epjb%2Fs10051-021-00245-1

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