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Distillability via protocols respecting the positivity of partial transpose

Tilo Eggeling·Karl Gerd H. Vollbrecht·Reinhard F. Werner·Michael M. Wolf
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Abstract

We show that all quantum states that do not have a positive partial transpose are distillable via channels, which preserve the positivity of the partial transpose. The question whether NPT bound entanglement exist is therefore closely related to the connection between the set of separable superoperators and PPT-preserving maps.

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Tilo Eggeling, Karl Gerd H. Vollbrecht, Reinhard F. Werner, Michael M. Wolf. 2001-05-14. Distillability via protocols respecting the positivity of partial transpose. https://doi.org/10.1103/physrevlett.87.257902

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