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Discrete Rotational Symmetry and Quantum Key Distribution Protocols

David Shirokoff·Chi-Hang Fred Fung·Hoi-Kwong Lo
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Abstract

We study the role of discrete rotational symmetry in quantum key distribution by generalizing the well-known Bennett-Brassard 1984 (BB84) and Scarani-Acin-Ribordy-Gisin 2004 (SARG04) protocols. We observe that discrete rotational symmetry results in the protocol's invariance to continuous rotations, thus leading to a simplified relation between bit and phase error rates and consequently a straightforward security proof.

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David Shirokoff, Chi-Hang Fred Fung, Hoi-Kwong Lo. 2006-12-22. Discrete Rotational Symmetry and Quantum Key Distribution Protocols. https://doi.org/10.1103/physreva.75.032341

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