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arXiv · 1808.03769

Quantum Fisher information and coherence in one-dimensional $XY$ spin models with Dzyaloshinsky-Moriya interactions

Biao-Liang Ye·Bo Li·Zhi-Xi Wang·Xianqing Li-Jost·Shao-Ming Fei
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Abstract

We investigate quantum phase transitions in $XY$ spin models using Dzyaloshinsky-Moriya (DM) interactions. We identify the quantum critical points via quantum Fisher information and quantum coherence, finding that higher DM couplings suppress quantum phase transitions. However, quantum coherence (characterized by the $l_1$-norm and relative entropy) decreases as the DM coupling increases. Herein, we present both analytical and numerical results.

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Biao-Liang Ye, Bo Li, Zhi-Xi Wang, Xianqing Li-Jost, Shao-Ming Fei. 2018-08-11. Quantum Fisher information and coherence in one-dimensional $XY$ spin models with Dzyaloshinsky-Moriya interactions. https://arxiv.org/abs/1808.03769

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