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arXiv · 2012.11986

Based-nonequilibrium-environment non-Markovianity, quantum Fisher information and quantum coherence

Danping Lin·Hong-Mei Zou·Jianhe Yang
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Abstract

In this work, we investigate the non-Markovianity, quantum Fisher information (QFI) and quantum coherence of a qubit in a nonequilibrium environment and have obtained the expressions of QFI and quantum coherence as well as their relationship. We have also discussed in detail the influences of the different noise parameters on these quantum sffects. The results show that the suitable parameters of the nonequilibrium environment can retard the QFI and quantum coherence in both Markovian and non-Markovian regions. In addition, the smaller memory effects and the larger the jumping rate, the greater the QFI and quantum coherence. And a larger QFI naturally corresponds to a larger quantum coherence, which indicates that the quantum coherence can enlarge the QFI and can effectively enhance the quantum metrology.

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Danping Lin, Hong-Mei Zou, Jianhe Yang. 2020-12-22. Based-nonequilibrium-environment non-Markovianity, quantum Fisher information and quantum coherence. https://doi.org/10.1088/1402-4896/ab4012

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