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Quantum correlations and secret bits

Antonio Acin·Nicolas Gisin
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Abstract

It is shown that (i) all entangled states can be mapped by single-copy measurements into probability distributions containing secret correlations, and (ii) if a probability distribution obtained from a quantum state contains secret correlations, then this state has to be entangled. These results prove the existence of a two-way connection between secret and quantum correlations in the process of preparation. They also imply that either it is possible to map any bound entangled state into a distillable probability distribution or bipartite bound information exists.

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Antonio Acin, Nicolas Gisin. 2005-02-16. Quantum correlations and secret bits. https://doi.org/10.1103/physrevlett.94.020501

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