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From Bell's Theorem to Secure Quantum Key Distribution

Antonio Acin·Nicolas Gisin·Lluis Masanes
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Abstract

Any Quantum Key Distribution (QKD) protocol consists first of sequences of measurements that produce some correlation between classical data. We show that these correlation data must violate some Bell inequality in order to contain distillable secrecy, if not they could be produced by quantum measurements performed on a separable state of larger dimension. We introduce a new QKD protocol and prove its security against any individual attack by an adversary only limited by the no-signaling condition.

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Antonio Acin, Nicolas Gisin, Lluis Masanes. 2005-10-13. From Bell's Theorem to Secure Quantum Key Distribution. https://doi.org/10.1103/physrevlett.97.120405

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