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arXiv · 2110.14530

Fully device-independent quantum key distribution using synchronous correlations

Nishant Rodrigues·Brad Lackey
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Abstract

We derive a device-independent quantum key distribution protocol based on synchronous correlations and their Bell inequalities. This protocol offers several advantages over other device-independent schemes including symmetry between the two users and no need for preshared randomness. We close a "synchronicity" loophole by showing that an almost synchronous correlation inherits the self-testing property of the associated synchronous correlation. We also pose a new security assumption that closes the "locality" (or "causality") loophole: an unbounded adversary with even a small uncertainty about the users' choice of measurement bases cannot produce any almost synchronous correlation that approximately maximally violates a synchronous Bell inequality.

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Nishant Rodrigues, Brad Lackey. 2021-10-27. Fully device-independent quantum key distribution using synchronous correlations. https://arxiv.org/abs/2110.14530

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