Experimental study of secure quantum key distribution with source and detection imperfections
Ye Chen, Chunfeng Huang, Zihao Chen, Wenjie He, Chengxian Zhang, Shi‐Hai Sun, Kejin Wei
Abstract
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 Bennett-Brassard 1984 (BB84) QKD experiment that considers both source and detection imperfections. In particular, we achieve 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.