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arXiv · 2208.03894

Experimental study of secure quantum key distribution with source and detection imperfections

Ye Chen·Chunfeng Huang·Zihao Chen·Wenjie He·Chengxian Zhang·Shihai Sun·Kejin Wei
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Abstract

The quantum key distribution (QKD), guaranteed by the principle of quantum physics, is a promising solution for future secure information and communication technology. However, device imperfections compromise the security of real-life QKD systems, restricting the wide deployment of QKD. This study reports a decoy-state BB84 QKD experiment that considers both source and detection imperfections. In particular, we achieved a rigorous finite-key security bound over fiber links of up to 75 km by applying a systematic performance analysis. Furthermore, our study considers more device imperfections than most previous experiments, and the proposed theory can be extended to other discrete-variable QKD systems. These features constitute a crucial step toward securing QKD with imperfect practical devices.

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Ye Chen, Chunfeng Huang, Zihao Chen, Wenjie He, Chengxian Zhang, Shihai Sun, Kejin Wei. 2022-08-08. Experimental study of secure quantum key distribution with source and detection imperfections. https://doi.org/10.1103/physreva.106.022614

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