硅光电倍增管(SiPM)光子数分辨性能受限于暗计数、光学串扰及高频信号堆积等,无法满足高速光子检测的需求。我们基于被动淬灭SiPM,采用了高通滤波放大与低噪声射频放大结合的方案,增强信号幅度的同时抑制基线漂移,在保障信号完整性的前...硅光电倍增管(SiPM)光子数分辨性能受限于暗计数、光学串扰及高频信号堆积等,无法满足高速光子检测的需求。我们基于被动淬灭SiPM,采用了高通滤波放大与低噪声射频放大结合的方案,增强信号幅度的同时抑制基线漂移,在保障信号完整性的前提下提升多光子雪崩事件的分辨率,实现了雪崩信号的大动态范围线性提取。高通滤波后,雪崩信号的下降时间从50.4 ns减小到3.7 ns,减少了雪崩的堆叠效应,拓宽了器件的响应带宽。在激光重复频率为10 MHz的条件下,实现了最多25个光子的光子数分辨。此外,SiPM输出信号的有效采集对其分辨性能至关重要,我们通过调节示波器垂直采样分辨率,确定了最适合信号采样的区间,为后续SiPM光子数可分辨探测器的集成设计以及动态范围优化提供支持。The photon-number-resolving capability of silicon photomultipliers (SiPM) is constrained by dark counts, optical crosstalk, and high-frequency signal pile-up, limiting their application in high-speed photon detection. In this study, we developed a solution for passive quenching SiPM by integrating high-pass filter amplification with low-noise radiofrequency amplification. This approach enhances signal amplitude while suppressing baseline drift, achieving high-resolution discrimination of multi-photon avalanche events and enabling linear extraction of avalanche signals across a wide dynamic range. After high-pass filter, the avalanche signal fall time was reduced from 50.4 ns to 3.7 ns, effectively mitigating avalanche pile-up effects and expanding the device bandwidth. Under 10 MHz laser repetition rate excitation, the system demonstrated photon-number resolution for up to 25 photons. Furthermore, the effective acquisition of the SiPM output signal is crucial to its resolution performance. We optimized signal acquisition by adjusting the vertical resolution of the oscilloscope to determine the optimal sampling parameters, providing critical guidance for the integrated design and dynamic range optimization of photon-number-resolving SiPM detectors.展开更多
为实现高能电子束发生轫致辐射产生的空间低强度脉冲X/γ射线的单粒子测量,本文基于近饱和放大时间过阈(time over threshold,TOT)技术,采用低带宽的运放和差分输出的甄别器,研制了一种用于硅光电倍增管(silicon photo-multiplier,SiPM...为实现高能电子束发生轫致辐射产生的空间低强度脉冲X/γ射线的单粒子测量,本文基于近饱和放大时间过阈(time over threshold,TOT)技术,采用低带宽的运放和差分输出的甄别器,研制了一种用于硅光电倍增管(silicon photo-multiplier,SiPM)的阵列型探测器全部通道读出的前端电子学系统。该系统能够获得能量、时间、强度等较为全面的物理信息,并在后端数字电路的FPGA内部通过脉宽和时间戳符合挑选出有效脉冲X/γ射线事件。本文详细介绍了前端电子学系统的设计方案、性能测试及功能验证等,并通过实验获得了低能区(50~200 keV)能量范围内的脉宽-能量谱和强度谱。测量结果表明:在低能区范围内,探测器阵列输出信号通过本文研制的前端电路处理后,脉宽和能量具有正相关关系,验证了脉冲X/γ射线有效事件识别的可行性;近饱和放大提高了定时精度,修正后可达800 ps。展开更多
文摘硅光电倍增管(SiPM)光子数分辨性能受限于暗计数、光学串扰及高频信号堆积等,无法满足高速光子检测的需求。我们基于被动淬灭SiPM,采用了高通滤波放大与低噪声射频放大结合的方案,增强信号幅度的同时抑制基线漂移,在保障信号完整性的前提下提升多光子雪崩事件的分辨率,实现了雪崩信号的大动态范围线性提取。高通滤波后,雪崩信号的下降时间从50.4 ns减小到3.7 ns,减少了雪崩的堆叠效应,拓宽了器件的响应带宽。在激光重复频率为10 MHz的条件下,实现了最多25个光子的光子数分辨。此外,SiPM输出信号的有效采集对其分辨性能至关重要,我们通过调节示波器垂直采样分辨率,确定了最适合信号采样的区间,为后续SiPM光子数可分辨探测器的集成设计以及动态范围优化提供支持。The photon-number-resolving capability of silicon photomultipliers (SiPM) is constrained by dark counts, optical crosstalk, and high-frequency signal pile-up, limiting their application in high-speed photon detection. In this study, we developed a solution for passive quenching SiPM by integrating high-pass filter amplification with low-noise radiofrequency amplification. This approach enhances signal amplitude while suppressing baseline drift, achieving high-resolution discrimination of multi-photon avalanche events and enabling linear extraction of avalanche signals across a wide dynamic range. After high-pass filter, the avalanche signal fall time was reduced from 50.4 ns to 3.7 ns, effectively mitigating avalanche pile-up effects and expanding the device bandwidth. Under 10 MHz laser repetition rate excitation, the system demonstrated photon-number resolution for up to 25 photons. Furthermore, the effective acquisition of the SiPM output signal is crucial to its resolution performance. We optimized signal acquisition by adjusting the vertical resolution of the oscilloscope to determine the optimal sampling parameters, providing critical guidance for the integrated design and dynamic range optimization of photon-number-resolving SiPM detectors.
