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arXiv · 0911.4245

Mixed State Entanglement Measures for Intermediate Separability

Tsubasa Ichikawa·Marcus Huber·Philipp Krammer·Beatrix C. Hiesmayr
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Abstract

To determine whether a given multipartite quantum state is separable with respect to some partition we construct a family of entanglement measures R_m. This is done utilizing generalized concurrences as building blocks which are defined by flipping of M constituents and indicate states that are separable with regard to bipartitions when vanishing. Further, we provide an analytically computable lower bound for R_m via a simple ordering relation of the convex roof extension. Using the derived lower bound, we illustrate the effect of the isotropic noise on a family of four-qubit mixed states for each intermediate separability.

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Tsubasa Ichikawa, Marcus Huber, Philipp Krammer, Beatrix C. Hiesmayr. 2009-11-24. Mixed State Entanglement Measures for Intermediate Separability. https://doi.org/10.1142/s0219749910006526

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