提高超导纳米线单光子探测器计数率的室温读出电路

Room-Temperature Readout Circuit for Improving Counting Rate of Superconducting Nanowire Single-Photon Detector

计数率是超导纳米线单光子探测器(SNSPD)的重要参数,介绍了一种在室温端提高SNSPD计数率的方法及其测量装置。首先,基于SNSPD系统的分布式电路模型,仿真分析了信号传输完整性和计数率的影响因素;进而,通过引入极低漏热柔性线解决信号完整性问题,实现在室温端串联电阻提升SNSPD计数率的系统。通过室温端串联150Ω的电阻,在不影响SNSPD系统探测效率以及暗计数率的基础上,器件的计数率提高5.3倍,该方法操作简单,可以满足实时提高SNSPD计数率的需求。

The counting rate(CR)is critical for superconducting nanowire singlephoton detector(SNSPD).This study presents a method for improving the CR of SNSPD at room temperature.Based on a distributed circuit model of the SNSPD system,the influencing factors of signal integrity and CR are simulated and analyzed.By introducing a flexible wire with very low heat leakage,the problem of signal integrity is solved,and the CR can be increased by the series resistor at room temperature.The CR of the device is increased by 5.3 times through a 150Ωseries resistor at room temperature without affecting the detection efficiency and dark count rate of the SNSPD system.The proposed method is simple and satisfies the requirements of increasing the CR of SNSPD in real time.