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Mixed-state entanglement and distillation: is there a ``bound'' entanglement in nature?

Michal Horodecki·Pawel Horodecki·Ryszard Horodecki
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Abstract

It is shown that if a mixed state can be distilled to the singlet form, it must violate partial transposition criterion [A. Peres, Phys. Rev. Lett. 76, 1413 (1996)]. It implies that there are two qualitatively different types of entanglement: ``free'' entanglement which is distillable, and ``bound'' entanglement which cannot be brought to the singlet form useful for quantum communication purposes. Possible physical meaning of the result is discussed.

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Michal Horodecki, Pawel Horodecki, Ryszard Horodecki. 1998-01-29. Mixed-state entanglement and distillation: is there a ``bound'' entanglement in nature?. https://doi.org/10.1103/physrevlett.80.5239

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