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Decoy state quantum key distribution with two-way classical post-processing

Xiongfeng Ma·Chi-Hang Fred Fung·Frédéric Dupuis·Kai Chen·Kiyoshi Tamaki·Hoi-Kwong Lo
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Abstract

Decoy states have recently been proposed as a useful method for substantially improving the performance of quantum key distribution protocols when a coherent state source is used. Previously, data post-processing schemes based on one-way classical communications were considered for use with decoy states. In this paper, we develop two data post-processing schemes for the decoy-state method using two-way classical communications. Our numerical simulation (using parameters from a specific QKD experiment as an example) results show that our scheme is able to extend the maximal secure distance from 142km (using only one-way classical communications with decoy states) to 181km. The second scheme is able to achieve a 10% greater key generation rate in the whole regime of distances.

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Xiongfeng Ma, Chi-Hang Fred Fung, Frédéric Dupuis, Kai Chen, Kiyoshi Tamaki, Hoi-Kwong Lo. 2006-04-12. Decoy state quantum key distribution with two-way classical post-processing. https://doi.org/10.1103/physreva.74.032330

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