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arXiv · 1007.1177

No-signaling, entanglement-breaking, and localizability in bipartite channels

Giacomo Mauro D'Ariano·Stefano Facchini·Paolo Perinotti
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Abstract

A bipartite quantum channel represents the interaction between systems, generally allowing for exchange of information. A special class of bipartite channels are the no-signaling ones, which do not allow communication. In Ref. [1] it has been conjectured that all no-signaling channels are mixtures of entanglement-breaking and localizable channels, which require only local operations and entanglement. Here we provide the general realization scheme, giving a counterexample to the conjecture.

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Giacomo Mauro D'Ariano, Stefano Facchini, Paolo Perinotti. 2010-07-20. No-signaling, entanglement-breaking, and localizability in bipartite channels. https://doi.org/10.1103/physrevlett.106.010501

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