Detection efficiency characteristics of free-running InGaAs/InP single photon detector using passive quenching active reset IC

InGaAs/InP avalanche photodiodes （APD） are rarely used in a free-running regime for near-infrared single photon detection. In order to overcome the detrimental afterpulsing, we demonstrate a passive quenching active reset integrated circuit. Taking advantage of the inherent fast passive quenching process and active reset to reduce reset time, the integrated circuit is useful for reducing afterpulses and is also area-efficient. We investigate the free-running single photon detector＇s afterpulsing effect, de-trapping time, dark count rate, and photon detection efficiency, and also compare with gated regime operation. After correction for deadtime and afterpulse, we find that the passive quenching active reset free-running single photon detector＇s performance is consistent with gated operation.

一种低检测阈值的高速主被动混合淬火电路设计

基于标准CMOS工艺,设计了一种用于单光子探测器的高速、低功耗主被动混合淬火电路。采用电流镜结构,设计一种低阈值快速比较器,将雪崩电流与阈值电流进行比较,以实现雪崩电流检测;比较器输出信号控制雪崩光电二极管的阳极电压,从而实现淬灭与恢复。采用Cadence软件,根据SPAD的SPICE模型,完成电路设计与仿真。结果表明,该淬火电路的淬灭时间为0.5 ns,恢复时间为1.34 ns,整体的死区时间为13.4 ns,检测阈值为1.3μA,功耗小于0.046 mW。