高稳定的差分相位编码量子密钥分发系统  

A highly stable differential phase shift key distribution QKD system

作　　者：李明明[1] 王发强[1] 路轶群[1] 赵峰[1] 陈霞[1] 梁瑞生[1] 刘颂豪[1] 

机构地区：[1]华南师范大学信息光电子科技学院光子信息技术广东省高校重点实验室,广州510631

出　　处：《物理学报》2006年第9期4642-4646,共5页Acta Physica Sinica

摘　　要：在差分法基础上提出了一种改进的差分相位编码量子密钥分发(QKD)方案.Alice采用脉冲激光光源,通过两个串联光纤延迟环产生四个均匀的相干脉冲,并对脉冲进行差分调制,补偿了传输过程中环境对偏振的扰动.Bob采用双FM干涉仪,在窄脉冲门控模式下进行单光子探测.单程传输避免了木马攻击,增强了方案的安全性.实验结果表明,系统可以长期稳定运转(大于24h),误码率为3%.改进的系统具有高效、稳定、低成本的优点,实施方便,有很好的实用价值.We propose and demonstrate an improved differential phase shift key distribution scheme. Alice uses a pulsed laser source and two cascaded fiber loops to get coherent pulses, then modulates them randomly under differential phase shift scheme, which compensates for the random polarization mode dispersion and phase shift. An interferometer made up of two Faraday mirrors is employed to detect single photon under gate mode. In one-way transmission, QKD is free from Trojan attack. Our experiment at setup can work stably for a long time （at least 24h） with an error ratio of 3 %. The stable scheme is efficient, economical and favorable for practical application.

关 键 词：量子保密通信 量子密钥分发 差分相位编码 

分 类 号：O431.2[机械工程—光学工程]