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arXiv · 2107.13916

Finite-size scaling of coherence and steered coherence in the Lipkin-Meshkov-Glick model

Ming-Liang Hu·Fan Fang·Heng Fan
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Abstract

Quantum coherence reflects the origin of quantumness and might be capable of extracting the subtle nature of a system. We investigate the ground-state coherence and steered coherence in the Lipkin-Meshkov-Glick model and show that they detect faithfully the quantum phase transitions of this model. Moreover, we carry out scaling analysis on the coherence and steered coherence by means of the continuous unitary transformation method and it is found that the scaling exponents are uniquely determined by the phase region of this model. These results may provide useful insights into the mechanism underlying quantum criticality in many-body systems.

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Ming-Liang Hu, Fan Fang, Heng Fan. 2021-07-29. Finite-size scaling of coherence and steered coherence in the Lipkin-Meshkov-Glick model. https://doi.org/10.1103/physreva.104.062416

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