量子密钥分发可以为通信双方提供无条件安全的密钥。提出使用压缩光源的无需监控信号干扰的量子密钥分发协议。该协议通过在接收端对量子信号进行循环移位并测量任意2个量子信号的相位差来实现量子密钥分发, 不仅可以产生安全密钥, 而且不需要监控信号干扰, 降低实现的复杂度。此外, 仅使用2种强度的诱骗态去估计安全密钥生成率。实验结果表明: 所提出的协议可以极大地提高安全密钥率, 并增大传输距离。此外, 仅使用2种强度的诱骗态也可以获得接近使用无穷个诱骗态的结果。

Quantum key distribution protocol can provide an unconditional secure key for two communication parties. This paper proposes a quantum key distribution protocol based on squeezed source without monitoring signal disturbance. The quantum key distribution is realized by cyclic shifting the quantum signal at the receiver and measuring the phase difference of any two quantum signals. This protocol can not only generate a secure key, but also do not need to monitor the signal disturbance so as to reduce the complexity of implementation. Moreover, a two-intensity decoy states method is applied into the proposed protocol to estimate the key rate. The experiment results show that both the maximum transmission distance and the security key rate of the proposed protocol is significantly improved. Moreover, only two-intensity decoy state is necessary for approaching the asymptotic limit with infinite decoy states in the proposed protocol.