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Security of quantum key distribution protocols using two-way classical communication or weak coherent pulses

Barbara Kraus·Cyril Branciard·Renato Renner
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Abstract

We apply the techniques introduced in [Kraus et. al., Phys. Rev. Lett. 95, 080501, 2005] to prove security of quantum key distribution (QKD) schemes using two-way classical post-processing as well as QKD schemes based on weak coherent pulses instead of single-photon pulses. As a result, we obtain improved bounds on the secret-key rate of these schemes.

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Barbara Kraus, Cyril Branciard, Renato Renner. 2006-10-18. Security of quantum key distribution protocols using two-way classical communication or weak coherent pulses. https://doi.org/10.1103/physreva.75.012316

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