提出并验证了一种基于光电倍增管单光子脉冲高度分布的多比特光量子随机源。将紫外LED发出的光衰减成离散的单光子序列,光电倍增管探测到的单光子后,输出脉冲幅度随机分布的单光子脉冲,通过数字化单光子脉冲的峰值作为熵源来提取随机数,实现了一个单光子事件产生多个随机比特位。为减小所提取原始随机数存在的偏差,提出并实现了基于FPGA的SHA-256后处理方法。光量子随机源工作在500kc/s时,平均每个探测光子可提取7bit随机位,获得了3.5 Mbit/s的随机位产生速率。运用随机性测试程序ENT和STS对所获的随机位序列进行测试,测试结果表明,序列的随机性满足真随机数的标准。
This paper proposes and demonstrates an optical quantum random number generator based on distribution of single photon pulse amplitude of a photomultiplier tube.The light emitted from ultraviolet LED is attenuated into discrete single photon sequence.After these photons are detected by the photomultiplier tube,the single-photon pulses with random distribution are output.Digital values of peaks of these single-photon pulses are used as the entropy sources of random number generation.In order to reduce the bias of the raw extracted random number,the SHA-256 post processing method based on FPGA is proposed and implemented.When our designed quantum random number generator works at a counting rate of 500kc/s,7random bits can be extracted on average per detected photon,and a random number generation rate of 3.5Mbit/s is obtained.The random bit sequences are tested by random number test programs ENT and STS.The test results show that the generated random bit sequences fully meet the standards of true random numbers.