arXiv:1703.07683 · Physical Review A

Gaussian two-mode attacks in one-way quantum cryptography

Carlo Ottaviani, Stefano Mancini, Stefano Pirandola

Published May 3, 2017• 15 citations

Abstract

We investigate the asymptotic security of one-way continuous variable quantum key distribution against Gaussian two-mode coherent attacks. The one-way protocol is implemented by arranging the channel uses in two-mode blocks. By applying symmetric random permutations over these blocks, the security analysis is in fact reduced to study two-mode coherent attacks and, in particular, Gaussian ones, due to the extremality of Gaussian states. We explicitly show that the use of two-mode Gaussian correlations by an eavesdropper leads to asymptotic secret key rates which are strictly larger than the rate obtained under standard single-mode Gaussian attacks.

DOI: 10.1103/physreva.95.052310

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