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arXiv · 1306.6184

Best Separable Approximation of multipartite diagonal symmetric states

Ruben Quesada·Anna Sanpera
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Abstract

The structural study of entanglement in multipartite systems is hindered by the lack of necessary and sufficient operational criteria able to discriminate among the various entanglement properties of a given mixed state. Here, we pursue a different route to the study of multipartite entanglement based on the closeness of a multipartite state to the set of separable ones. In particular, we analyze multipartite diagonal symmetric N qubit states and provide the analytical expression for their Best Separable Approximation (BSA [Phys. Rev. Lett. 80, 2261 (1998)]), that is, their unique convex decomposition into a separable part and an entangled one with maximal weight of the separable one.

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Ruben Quesada, Anna Sanpera. 2014-05-19. Best Separable Approximation of multipartite diagonal symmetric states. https://doi.org/10.1103/physreva.89.052319

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