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Characterization and quantification of symmetric Gaussian state entanglement through a local classicality criterion

M. C. de Oliveira
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Abstract

A necessary and sufficient condition for characterization and quantification of entanglement of any bipartite Gaussian state belonging to a special symmetry class is given in terms of classicality measures of one-party states. For Gaussian states whose local covariance matrices have equal determinants it is shown that separability of a two-party state and classicality of one party state are completely equivalent to each other under a nonlocal operation, allowing entanglement features to be understood in terms of any available classicality measure.

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M. C. de Oliveira. 2005-07-21. Characterization and quantification of symmetric Gaussian state entanglement through a local classicality criterion. https://doi.org/10.1103/physreva.72.012317

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