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arXiv · 1205.0959

Improving the maximum transmission distance of continuous-variable quantum key distribution using a noiseless amplifier

Rémi Blandino·Anthony Leverrier·Marco Barbieri·Jean Etesse·Philippe Grangier·Rosa Tualle-Brouri
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Abstract

We show that the maximum transmission distance of continuous-variable quantum key distribution in presence of a Gaussian noisy lossy channel can be arbitrarily increased using a linear noiseless amplifier. We explicitly consider a protocol using amplitude and phase modulated coherent states with reverse reconciliation. We find that a noiseless amplifier with amplitude gain g can increase the maximum admissible losses by a factor 1/g^2.

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Rémi Blandino, Anthony Leverrier, Marco Barbieri, Jean Etesse, Philippe Grangier, Rosa Tualle-Brouri. 2012-05-04. Improving the maximum transmission distance of continuous-variable quantum key distribution using a noiseless amplifier. https://doi.org/10.1103/physreva.86.012327

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