The private classical capacity with a symmetric side channel and its application to quantum cryptography

dc.creatorSmith, Graeme
dc.date2007-05-25
dc.date.accessioned2026-07-07T09:54:51Z
dc.date.available2026-07-07T09:54:51Z
dc.descriptionWe study the symmetric-side-channel-assisted private capacity of a quantum channel, for which we provide a single-letter formula. This capacity is additive, convex, and, for degradable channels, equal to the unassisted private capacity. While a channel's (unassisted) capacity for for private classical communication may be strictly larger than its quantum capacity, we will show that these capacities are equal for degradable channels, thus demonstrating the equivalence of privacy and quantum coherence in this context. We use these ideas to find new bounds on the key rate of quantum key distribution protocols with one-way classical post-processing. For the Bennett-Brassard-84 (BB84) protocol, our results demonstrate that collective attacks are strictly stronger than individual attacks.
dc.description8 pages, 1 figure
dc.identifierhttps://arxiv.org/abs/0705.3838
dc.identifierhttp://arxiv.org/abs/0705.3838
dc.identifierPhys. Rev. A 78, 022306 (2008)
dc.identifierdoi:10.1103/PhysRevA.78.022306
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/166469
dc.subjectQuantum Physics
dc.titleThe private classical capacity with a symmetric side channel and its application to quantum cryptography
dc.typetext

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