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Multipartite continuous-variable entanglement

E. Shchukin·W. Vogel
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Abstract

Necessary and sufficient observable conditions for the nonnegativity of all partial transpositions of multi-mode quantum states are derived. The result is a hierarchy of inequalities for minors in terms of moments of the given state. Violations of any inequality is a sufficient condition for entanglement. Full entanglement can be certified for a manifold of multi-mode quantum states. A \textit{Mathematica} package is given for a systematic test of the hierarchy of conditions.

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E. Shchukin, W. Vogel. 2006-05-17. Multipartite continuous-variable entanglement. https://doi.org/10.1103/physreva.74.030302

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