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arXiv · 1310.7768

Multipartite quantum correlations in even and odd spin coherent states

M. Daoud·R. Ahl Laamara·W. Kaydi
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Abstract

The key ingredient of the approach, presented in this paper, is the factorization property of $SU(2)$ coherent states upon splitting or decay of a quantum spin system. In this picture, the even and odd spin coherent states are viewed as comprising two, three or more spin subsystems. From this perspective, we investigate the multipartite quantum correlations defined as the sum of the correlations of all possible bi-partitions. The pairwise quantum correlations are quantified by entanglement of formation and quantum discord. A special attention is devoted to tripartite splitting schemes. We explicitly derive the sum of entanglement of formation for all possible bi-partitions. It coincides with the sum of all possible pairwise quantum discord. The conservation relation between the distribution of entanglement of formation and quantum discord, in the tripartite splitting scheme, is discussed. We show that the entanglement of formation and quantum discord possess the monogamy property for even spin coherent states, contrarily to odd ones which violate the monogamy relation when the the overlap of the coherent states approaches the unity.

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M. Daoud, R. Ahl Laamara, W. Kaydi. 2013-10-29. Multipartite quantum correlations in even and odd spin coherent states. https://doi.org/10.1088/1751-8113%2F46%2F39%2F395302

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