Chen Sijing, You Lixing, Zhang Weijun, Yang Xiaoyan, Li Hao, Zhang Lu, Wang Zhen, Xie Xiaoming
Opt Express. 2015 Apr 20;23(8):10786-93. doi: 10.1364/OE.23.010786.
An abnormal increase in the SDE was observed for superconducting nanowire single-photon detectors (SNSPDs) when the bias current (I(b)) was close to the switching current (I(sw)). By introducing the time-correlated single-photon counting technique, we investigated the temporal histogram of the detection counts of an SNSPD under illumination. The temporal information helps us to distinguish photon counts from dark counts in the time domain. In this manner, the dark count rate (DCR) under illumination and the accurate SDE can be determined. The DCR under moderate illumination may be significantly larger than the conventional DCR measured without illumination under a high I(b), which causes the abnormal increase in the SDE. The increased DCR may be explained by the suppression of I(sw) under illumination.
当偏置电流（I(b)）接近开关电流（I(sw)）时，观察到超导纳米线单光子探测器（SNSPD）的超动态效应（SDE）出现异常增加。通过引入时间相关单光子计数技术，我们研究了SNSPD在光照下检测计数的时间直方图。时间信息有助于我们在时域中将光子计数与暗计数区分开来。通过这种方式，可以确定光照下的暗计数率（DCR）和准确的SDE。中等光照下的DCR可能显著大于在高I(b)下无光照时测量的传统DCR，这导致了SDE的异常增加。增加的DCR可以用光照下I(sw)的抑制来解释。
