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arXiv · 0704.2597

Separability, entanglement and full families of commuting normal matrices

Jan Samsonowicz·Marek Kus·Maciej Lewenstein
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Abstract

We reduce the question whether a given quantum mixed state is separable or entangled to the problem of existence of a certain full family of commuting normal matrices whose matrix elements are partially determined by components of the pure states constituting a decomposition of the considered mixture. The method reproduces many known entanglement and/or separability criteria, and provides yet another geometrical characterization of mixed separable states.

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Jan Samsonowicz, Marek Kus, Maciej Lewenstein. 2007-06-27. Separability, entanglement and full families of commuting normal matrices. https://doi.org/10.1103/physreva.76.022314

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