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arXiv · 1702.03123

One-way quantum deficit and quantum coherence in the anisotropic $XY$ chain

Biao-Liang Ye·Bo Li·Li-Jun Zhao·Hai-Jun Zhang·Shao-Ming Fei
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Abstract

In this study, we investigate pairwise non-classical correlations measured using a one-way quantum deficit as well as quantum coherence in the $XY$ spin-1/2 chain in a transverse magnetic field for both zero and finite temperatures. The analytical and numerical results of our investigations are presented. In the case when the temperature is zero, it is shown that the one-way quantum deficit can characterize quantum phase transitions as well as quantum coherence. We find that these measures have a clear critical point at $\lambda=1$. When $\lambda\le1$, the one-way quantum deficit has an analytical expression that coincides with the relative entropy of coherence. We also study an $XX$ model and an Ising chain at the finite temperatures.

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Biao-Liang Ye, Bo Li, Li-Jun Zhao, Hai-Jun Zhang, Shao-Ming Fei. 2017-02-10. One-way quantum deficit and quantum coherence in the anisotropic $XY$ chain. https://arxiv.org/abs/1702.03123

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