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arXiv · 1612.08339

Protecting coherence in the non-Hermitian two-level system

Wei-Chen Wang·Mao-Fa Fang
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Abstract

We have constructed a non-Hermitian two-level system (a PT -symmetric system) in dissipative environments, and investigated the quantum coherence in the non-Hermitian two-level system. Our results show that, quantum coherence can be created by PT -symmetric systems, even if the initial state of the twolevel system is incoherent state. Even though two-level system is interacted with dissipative environments, the quantum coherence exhibits a long-lived revival, and can be protected. We find that the two-level system can obtain more coherence with the coupling strength {\Omega} increases. And we should point out that the PT -symmetric system can be regarded as a good candidate system for creation of the long-lived quantum coherence in dissipative environments.

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Wei-Chen Wang, Mao-Fa Fang. 2016-12-26. Protecting coherence in the non-Hermitian two-level system. https://arxiv.org/abs/1612.08339

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