【摘要】 对双非对称Mach-Zehnder干涉仪量子密钥分发系统的误码率做了系统的理论分析。详细分析了两 Mach-Zehnder干涉仪臂长的不对称性、光纤的双折射以及环境温度等因素对误码率的影响,并导出了定量的数学表达式。研究结果表明,两个Mach-Zehnder干涉仪臂长的不对称引起的误码率服从高斯分布;由光纤双折射引起光脉冲干涉时偏振方向不一致引起的误码率服从正弦分布;干涉仪中的温度变化对误码产生极大的影响。更多还原

【Abstract】 Quantum bit error rate (QBER) of the quantum key distribution system based on the unbalanced Mach-Zehnder interferometer is theoretically analyzed. The influence of the unsymmetry of the two Mach-Zehnder interferometers, the birefringence in the fiber and the fluctuation of the temperature, on the QBER have been discussed in detail. The analytical expression of the QBER is deduced. It shows that the QBER caused by the unsymmetry of the two Mach-Zehnder interferometers defers to the Gauss distribution, QBER caused by the birefringence in the fiber which results in the disaccord of the polarization of the two pulses defers to the cosine distribution, and the fluctuation of the temperature exert great influence on the QBER.更多还原