Yang-Guang Shan

Quantum key distribution (QKD) provides theoretical secure solutions to realize remote key distribution. However, there are many kinds of device loopholes giving rise to a great obstacle to its practical security. Some existing studies have addressed certain vulnerabilities. But it is hard to eliminate all potential loopholes while maintaining high performance. In this article, we propose a new QKD protocol called phase-coding side-channel-secure (PC-SCS) protocol. This protocol can be immune to all uncorrelated side channels of the source part and all loopholes of the measurement part. A finite-key security analysis against coherent attack of the new protocol is given. The proposed protocol only requires modulation of two phases, which can avoid the challenge of preparing perfect vacuum states. Numerical simulation shows that a practical transmission distance of 300 km in fiber can be realized by the PC-SCS protocol.