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arXiv · quant-ph/9605038

Separability of Mixed States: Necessary and Sufficient Conditions

Michal Horodecki·Pawel Horodecki·Ryszard Horodecki
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Abstract

We provide necessary and sufficient conditions for separability of mixed states. As a result we obtain a simple criterion of separability for $2\times2$ and $2\times3$ systems. Here, the positivity of the partial transposition of a state is necessary and sufficient for its separability. However, it is not the case in general. Some examples of mixtures which demonstrate the utility of the criterion are considered.

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Michal Horodecki, Pawel Horodecki, Ryszard Horodecki. 1996-06-26. Separability of Mixed States: Necessary and Sufficient Conditions. https://doi.org/10.1016/s0375-9601(96)00706-2

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