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On Multipartite Pure-State Entanglement

Ashish V. Thapliyal
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Abstract

We show that pure states of multipartite quantum systems are multiseparable (i.e. give separable density matrices on tracing any party) if and only if they have a generalized Schmidt decomposition. Implications of this result for the quantification of multipartite pure-state entanglement are discussed. Further, as an application of the techniques used here, we show that any purification of a bipartite PPT bound entangled state is tri-inseparable, i.e. has none of its three bipartite partial traces separable.

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Ashish V. Thapliyal. 1999-02-18. On Multipartite Pure-State Entanglement. https://doi.org/10.1103/physreva.59.3336

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