双协议量子密钥分发系统实验研究  

Experimental quantum key distribution with double protocol

作　　者：胡华鹏[1] 张静[1] 王金东[1] 黄宇娴[1] 路轶群[1] 刘颂豪[1] 路巍[2] 

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510006 [2]中国科学院合肥智能研究所,合肥230031

出　　处：《物理学报》2008年第9期5605-5611,共7页Acta Physica Sinica

基　　金：国家重点基础研究发展规划(973)项目(批准号:2007CB307001)资助的课题~~

摘　　要：提出了一种改进的基于时间和相位混合编码的量子密钥分发方案,并进行了实验研究.在以BB84协议为基础的相位编码量子密钥分发系统上,利用了系统中原来舍弃的脉冲进行时间编码,使成码率提高为原方案的二倍.系统同时获得时间编码密钥和相位编码密钥,现在可以将两组密钥组合成新密钥,提高了成码率和监测窃听灵敏度.同时在系统的接收端用双FM反射式干涉仪代替传统的光纤M-Z干涉仪,提高了系统的稳定性.实验上已实现90 km光纤量子密钥分发,实验表明本系统具有安全性高,稳定性好,成本低的优点.We propose one kind of improved QKD scheme based on time coding and phase coding. The pulse which had been discarded on the BB84 protocol phase coding QKD system is used to realize the time coding protocol, thus the useful bits rate in the present scheme can be doubled. At the same time, the phase coding keys and the time coding keys are obtained, we may combine both as new keys which can enhance the generated rate and the sensitivity of monitor. At Bob＇ s side, a Fraday- Michelson is used instead of a traditional M-Z interferometer, which improves the stability of the interference visibility. With the proposed experimental setup, a stable quantum key distribution was performed over 90 km fiber. It is shown in our experiment that the characteristics of our system are as follows： secure, stable and economical.

关 键 词：量子保密通信 量子密钥分发 相位编码 时间编码 

分 类 号：O413.1[理学—理论物理]