面向SNSPD系统的可拓展时间抖动测量模块

Scalable time jitter measurement module for SNSPD system

摘要:

针对超导纳米线单光子探测器（SNSPD）应用需求的多样化，设计了一款面向SNSPD的可拓展时间抖动测量模块。基于对SNSPD系统时间抖动测量原理的分析，设计了数字化单元、时间数字转换（TDC）单元和现场可编程门阵列（FPGA）单元，实现对SNSPD输出信号的数字化、时间信息测量以及数据读取。对该模块TDC单元的分辨率、线性度和时间精度分别标定，测试结果表明TDC单元的分辨率好于55ps，测量数据呈线性，100ns以内时间精度低于36ps。通过结合实用化SNSPD系统，实现了100ps左右的时间抖动表征，并与商用时间相关单光子计数（TCSPC）模块对比，验证了该模块对于SNSPD系统时间抖动测量的可行性。

Abstract:

A scalable time jitter measurement module for SNSPDs is designed to address the diverse application requirements of superconducting nanowire single photon detectors (SNSPDs). Based on the analysis of the time jitter measurement principle of the SNSPD system, a digitisation unit, a time-to-digital conversion (TDC) unit and a field-programmable gate array (FPGA) unit are designed to digitise the SNSPD output signal, measure the time information and read out the data. The resolution, linearity and time accuracy of the TDC unit of the module were calibrated and the test results showed that the resolution of the TDC unit was better than 55 ps, the measurement data was linear and the time accuracy within 100 ns was less than 36 ps. By combining the practical SNSPD system, a time jitter characterisation of about 100 ps was achieved and compared with a commercial time-correlated single photon counting (TCSPC) module. The feasibility of this module for time jitter measurements in SNSPD systems is verified by comparison with a commercial time-correlated single photon counting (TCSPC) module.