摘要
InGaAs半导体单光子探测器具备探测性能强,集成度高等优势,在光谱分析和量子通信等领域有广泛的应用.本文以ID Quantique公司出品的ID-201半导体单光子计数器为研究对象,结合计数器核心部件雪崩光电二极管的工作原理探究其计数光子时的内部过程,推导出每秒钟光子计数值和该计数器几个重要参数触发频率(trigger frequency),门脉冲宽度(gate width),门强制关闭时间(dead time),探测效率(detection efficiency)之间的数学表达式.推导过程着重分析了计数门脉冲的关闭效应对光子探测概率的影响.首先利用泊松分布求解光子计数值与探测效率(detection efficiency)之间的关系,然后将计数过程分成两大部分,分析计数结果与门强制关闭时间(dead time)之间关系.求解得表达式后,利用1550nm激光器作为ID-201的输入光源,在各种不同实验条件下,对该表达式的正确性进行了检验.
The technology of photon counting has wide applications in physics and electrical engineering.Single photon detectors based on avalanche photodiodes are attractive,Considering their advantages including compact sizes,broad spectrum of responses,and high detection efficiencies.The semiconductor single photon detector normally works in the gated mode,where photons can only be detected when the gate is open.However,if any photon is detected by the photon counter during the gate,several gates after the detection will be forced to shut down so that no photon can be detected during this period.The timing duration that the gates are down is called the dead time.This article mainly focuses on the photon counting performance of the ID-201 semiconductor photon counter,which is produced by the ID Quantique company.The purpose is to derive a photon counting formula for ID-201 and verify it using experiments.Starting with a simple Poisson distribution,we first studied the relationship between the detection probability and the average numbers of the photons when the dead time effect was absent.Next,we examined the effect of the dead time by separating the general counting processes of ID-201 into two different types,for which the photon detection probabilities could be easily calculated.Finally,based on the above analysis methods,we successfully derived a mathematical formula that related the photon counts per second to several important parameters such as the opticalpower,the trigger frequency,the gate width,the detection efficiency and the dead time.To verify the derived formula,a series of experiments were performed using the ID-201 in together with a power-adjustable fiber-optic light source that operated at 1550 nm.It is found that under different conditions,the derived formula well agree with the experimental results.
出处
《南京大学学报（自然科学版）》
CAS
CSCD
北大核心
2016年第3期550-557,共8页
Journal of Nanjing University（Natural Science）
