【摘要】 该单光子探测器在实验中使用半导体制冷器制冷,雪崩二极管工作于盖革模式下,使用交流耦合方式提供门脉冲信号,通过延迟补偿和采样门控消除尖脉冲干扰,采用反馈门控减小后脉冲影响,优化电路参数减小暗计数.经实验测试与分析,温度在-62.5℃,门脉冲宽度为50ns,采样门控为10ns的条件下,最佳工作点的暗计数率小于4×10-6ns-1,量子效率约18%,噪声等效功率为2.4×10-19W/Hz1/2.更多还原

【Abstract】 A single photon detector operating in the Geiger mode is cooled to a moderate temperature by using Peltier cooling, and a gate pulse is coupled to the avalanche diode through capacitance. It uses a moderate delay and sampling gate modulation to prevent the positive and the negative transient pulses from influencing the detection of true photon avalanches, a dead time modulation feedback control circuit to suppress the afterpulsing, and an optimized circuit to reduce the dark counts. The performance test shows that at the optimum operation point the quantum efficiency is about 18%, the dark count rate is less than 4×10~ -6 ns~ -1 and the noise-equivalent power is 2.4×10~-19 W/Hz~ 1/2 .更多还原