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Violation of Bell's inequalities implies distillability for N qubits

A. Acin·V. Scarani·M. M. Wolf
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Abstract

We consider quantum systems composed of $N$ qubits, and the family of all Bell's correlation inequalities for two two-valued measurements per site. We show that if a $N$-qubit state $ρ$ violates any of these inequalities, then it is at least bipartite distillable. Indeed there exists a link between the amount of Bell's inequality violation and the degree of distillability. Thus, we strengthen the interpretation of Bell's inequalities as detectors of useful entanglement.

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A. Acin, V. Scarani, M. M. Wolf. 2002-09-02. Violation of Bell's inequalities implies distillability for N qubits. https://doi.org/10.1088/0305-4470%2F36%2F2%2F101

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