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arXiv · 1703.10775

Dark state with counter-rotating dissipative channels

Zheng-yang Zhou·Mi Chen·Lian-Ao Wu·Ting Yu·J. Q. You
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Abstract

Dark state as a consequence of interference between different quantum states has great importance in the fields of chip-scale atomic clock and quantum information. For the $Λ$-type three-level system, this dark state is generally regarded as being dissipation-free because it is a superposition of two lowest states without dipole transition between them. However, previous studies are based on the rotating-wave approximation (RWA) by neglecting the counter-rotating terms in the system-environment interaction. In this work, we study non-Markovian quantum dynamics of the dark state in a $Λ$-type three-level system coupled to two bosonic baths and reveal the effect of counter-rotating terms on the dark state. In contrast to the dark state within the RWA, leakage of the dark state occurs even at zero temperature, as a result of these counter-rotating terms. Also, we present a method to restore the quantum coherence of the dark state by applying a leakage elimination operator to the system.

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Zheng-yang Zhou, Mi Chen, Lian-Ao Wu, Ting Yu, J. Q. You. 2017-06-05. Dark state with counter-rotating dissipative channels. https://arxiv.org/abs/1703.10775

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