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Cloning and Optimal Gaussian individual attacks for continuous-variable quantum key distribution using coherent states and reverse reconciliation

Ryo Namiki·Masato Koashi·Nobuyuki Imoto
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Abstract

We investigate the security of continuous-variable (CV) quantum key distribution (QKD) using coherent states and reverse reconciliation against Gaussian individual attacks based on an optimal Gaussian $1 \to 2$ cloning machine. We provide an implementation of the optimal Gaussian individual attack. we also find a Bell-measurement attack which works without delayed choice of measurements and has better performance than the cloning attack.

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Ryo Namiki, Masato Koashi, Nobuyuki Imoto. 2005-12-10. Cloning and Optimal Gaussian individual attacks for continuous-variable quantum key distribution using coherent states and reverse reconciliation. https://doi.org/10.1103/physreva.73.032302

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