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arXiv · 0904.1327

Security bound of continuous-variable quantum key distribution with noisy coherent states and channel

Yong Shen·Jian Yang·Hong Guo
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Abstract

Security of a continuous-variable quantum key distribution protocol based on noisy coherent states and channel is analyzed. Assuming the noise of coherent states is induced by Fred, a neutral party relative to others, we prove that the prepare and measurement scheme and entanglement-based scheme are equivalent. Then, we show that this protocol is secure against Gaussian collective attacks even if the channel is lossy and noisy, and further, a lower bound to the secure key rate is derived.

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Yong Shen, Jian Yang, Hong Guo. 2009-04-08. Security bound of continuous-variable quantum key distribution with noisy coherent states and channel. https://doi.org/10.1088/0953-4075/42/23/235506

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