量子密钥分发系统中增益开关半导体激光器的时间抖动分析  

Timing Jitter of Gain-switched Laser Diodes in Quantum Key Distribution System

作　　者：方俊彬[1] 廖常俊[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510006

出　　处：《河南师范大学学报（自然科学版）》2008年第3期52-55,共4页Journal of Henan Normal University(Natural Science Edition)

基　　金：国家重点基础研究发展计划(973)项目(G2001039302);广东省自然科学基金(2003A1030405)

摘　　要：.针对量子密钥分发系统中用于产生微弱激光脉冲的增益开关半导体激光器存在时间抖动较大的问题,首先建立了单光子探测的概率分布与光脉冲的能量分布的对应关系,采用速率方程和数值计算方法研究了时间抖动对增大单光子丢失概率的直接作用以及随激光器偏置电流变化的关系,并从降低时间抖动和减少单光子丢失概率的角度给出了合适的偏置条件.Gain-switched laser diodes, which suffer from serious timing jitter, are wildly used in quantum key distribution to generate faint laser pulses. In this paper, the relationship between energy distribution in laser pulses and probability distribution of single photon detection is built firstly. Based on the relation, the effect of timing jitter on increasing the loss probabil- ity of single photon is studied by using rate equations and numerical simulation. Furthermore, the variation of time jitter and loss probability when bias current is adjusted is also analyzed carefully. Lastly, the paper suggests the proper bias condition in the sense of decreasing time jitter and reducing loss probability of single photon.

关 键 词：量子密钥分发 时间抖动 增益开关半导体激光器 

分 类 号：O439[机械工程—光学工程]