arXiv:quant-ph/9801069 · Physical Review Letters

Mixed-State Entanglement and Distillation: Is there a “Bound” Entanglement in Nature?

Michał Horodecki, Paweł Horodecki, Ryszard Horodecki

Published Jun 15, 1998• 1,208 citations

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. A possible physical meaning of the result is discussed.

DOI: 10.1103/physrevlett.80.5239

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