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Environment assisted entanglement enhancement

Biplab Ghosh·A. S. Majumdar·N. Nayak
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Abstract

We consider dissipative atom-cavity systems and show that their collective dynamics leads to the maximization of entanglement for intermediate values of the cavity leakage parameter $κ$. We discuss possible ways the reservoir influences entanglement. We first consider the entanglement of a single two-level atom with a microwave cavity that is coupled to another cavity. We show that the atom-cavity entanglement can be made to increase with cavity leakage. We next show that the entanglement between two atoms passing successively through a cavity can be maximised for intermediate values of $κ$. We finally consider the micromaser where the increase of two-atom entanglement for stronger cavity-environment coupling is demonstrated for experimentally attainable values of the micromaser parameters.

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Biplab Ghosh, A. S. Majumdar, N. Nayak. 2006-12-22. Environment assisted entanglement enhancement. https://doi.org/10.1103/physreva.74.052315

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