量子密钥分配协议的安全性主要是指在一定信道条件下协议所能支持的最高安全密钥生成率,而退极化信道则是量子信息理论中一种常用的信道模型,该模型可以有效刻画量子态在量子信道传输中的扰动。利用量子信息论方法推导并模拟了退极化信道条件下BB84协议与设备无关协议的安全性。对于给定的退极化信道参数和信道衰减参数,进一步结合诱骗态方案给出了两种协议在不同信道传输距离下的安全密钥率。该研究结果可用于理论模拟在长距离量子密钥分配条件下的安全密钥生成率,为进一步的安全性分析和实验实现建立了理论基础。

The security performance of quantum key distribution protocol mainly refers to the maximum secure key generation rate that the protocol can support under certain channel conditions. Depolarization channel is a common channel model in quantum information theory, which can effectively illustrate the disturbance of quantum states transmission in quantum channel. The security performance of BB84 protocol and device-independent protocol in depolarization channel is deduced and simulated by using quantum information theory. For the given depolarization quantum channel parameters and channel attenuation parameters, the security key rates of the two protocols under different channel transmission distances are given in combination with the decoy state scheme. The results can be used to theoretically simulate the security key generation rate under the condition of long-distance quantum key distribution, which establishes the theoretical basis for further security analysis and experimental implementation.