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arXiv · 2103.11496

Effective protection of quantum coherence by non-Hermitian driving

Kai-Qian Huang·Wen-Lei Zhao·Zhi Li
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Abstract

In this letter, we investigate the effects of non-Hermitian driving on quantum coherence in a bipartite system. The results that the dynamical localization destroyed by the Hermitian interaction revives are an evidence of the restoration of quantum coherence by non-Hermitian driving. Besides, the entanglement between the two subsystems also decays with the boosting of non-hermitian driving strength, which provides another evidence that non-Hermitian driving will protect quantum coherence. The physics behind this phenomenon is the domination of the quasieigenstate with maximum imaginary value of the quasieigenvalue on the dynamics of the non-Hermitian system. Our discovery establishes a restoration mechanism of quantum coherence in interacting and dissipative quantum systems, which is highly relevant to experiments in diverse fields from many-body physics to quantum information.

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Kai-Qian Huang, Wen-Lei Zhao, Zhi Li. 2021-03-21. Effective protection of quantum coherence by non-Hermitian driving. https://doi.org/10.1103/physreva.104.052405

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