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arXiv · 1912.12734

The effect of nonequilibrium entropy production on the quantum Fisher information and correlations

Xuanhua Wang·Jin Wang
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Abstract

In this study, we apply quantum master equations beyond secular approximation, and investigate the nonequilibrium thermodynamic cost of enhanced quantum metrology and quantum correlations. We find that the nonequilibrium conditions enhance quantum Fisher information (QFI) and quantum correlations predominantly for weak tunneling scenarios. The enhancement is assisted by a corresponding increase of the thermodynamic cost characterized by the entropy production rate (EPR). For the strong tunneling regimes, the QFI and quantum correlations can not be unceasingly boosted by higher thermodynamic costs and decay once the system is overburdened with extremely large energy currents. The result indicates that for open systems with weak tunneling rates, thermodynamic cost can be potentially exploited to improve the quantum metrology and quantum correlations.

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Xuanhua Wang, Jin Wang. 2019-12-29. The effect of nonequilibrium entropy production on the quantum Fisher information and correlations. https://arxiv.org/abs/1912.12734

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