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.
@article{arxiv.quant-ph/0604094,
title = {Decoy state quantum key distribution with two-way classical post-processing},
author = {Xiongfeng Ma and Chi-Hang Fred Fung and Frédéric Dupuis and Kai Chen and Kiyoshi Tamaki and Hoi-Kwong Lo},
journal= {arXiv preprint arXiv:quant-ph/0604094},
year = {2016}
}