一种基于确定性量子密钥分发误码判据的相位调制器半波电压的精确测定方法

基于相位编码的量子密钥分发系统需要对信息加载的相位调制器的半波电压进行精确的测定以减小量子密钥的误码率,相位调制器半波电压的测量精度直接影响到了量子密钥分发系统的最终误码.本文提出了一种基于确定性量子密钥分发误码率判据的相位调制器半波电压的精确测定方法,所采用相位调制器的半波电压的测量精度达到了2mV,实验结果表明这种方法可以用于量子密钥分发实际应用系统中实时获得不同条件下的行波相位调制器的半波电压以最大程度地减小由于相位信息不准确加载而带来的系统误码.

A new method to acquire the half-wave voltage by the quantum bit error rate in the deterministic quantum key distribution system

The value of the half-wave voltage of the phase modulator must be measured with high accuracy to reduce the quantum bit error rate (QBER) in a quantum key distribution system based the phase-coding scheme. A new method to measure the half-wave voltage of the phase modulator in an accuracy of 2 mV by adjusting the quantum bit error rate (QBER) of the deterministic quantum key distribution is proposed experimentally to increase the accuracy of the half-wave voltage and reduce the error rate of the quantum key distribution system. The experimental results show that this method can be used to acquire efficiently the half-wave voltage of the phase modulator in a high accuracy which can make the error rate from adding the inaccurate voltage to the phase modulator decrease to the greatest extent.