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arXiv · 1504.07093

Unidimensional continuous-variable quantum key distribution

Vladyslav C. Usenko·Frédéric Grosshans
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Abstract

We propose the continuous-variable quantum key distribution protocol based on the Gaussian modulation of a single quadrature of the coherent states of light, which is aimed to provide simplified implementation compared to the symmetrically modulated Gaussian coherent-state protocols. The protocol waives the necessity in phase quadrature modulation and the corresponding channel transmittance estimation. The security of the protocol against collective attacks in a generally phase-sensitive Gaussian channels is analyzed and is shown achievable upon certain conditions. Robustness of the protocol to channel imperfections is compared to that of the symmetrical coherent-state protocol. The simplified unidimensional protocol is shown possible at a reasonable quantitative cost in terms of key rate and of tolerable channel excess noise.

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Vladyslav C. Usenko, Frédéric Grosshans. 2016-01-11. Unidimensional continuous-variable quantum key distribution. https://doi.org/10.1103/physreva.92.062337

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