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Multipartite Entanglement and Quantum State Exchange

D. T. Pope·G. J. Milburn
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Abstract

We investigate multipartite entanglement in relation to the theoretical process of quantum state exchange. In particular, we consider such entanglement for a certain pure state involving two groups of N trapped atoms. The state, which can be produced via quantum state exchange, is analogous to the steady-state intracavity state of the subthreshold optical nondegenerate parametric amplifier. We show that, first, it possesses some 2N-way entanglement. Second, we place a lower bound on the amount of such entanglement in the state using a novel measure called the entanglement of minimum bipartite entropy.

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D. T. Pope, G. J. Milburn. 2004-02-27. Multipartite Entanglement and Quantum State Exchange. https://doi.org/10.1103/physreva.67.052107

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