超低暗计数率硅单光子探测器的实现

Realization of Silicon Single-Photon Detector with Ultra-Low Dark Count Rate

研究了在Geiger模式下工作的单光子雪崩二极管的温度特性。结果表明,该雪崩二极管的雪崩电压随温度的降低呈线性减小,电压温度系数为0.42 V/K。当该雪崩二极管在13 V以上雪崩电压下工作时,暗计数率随着温度的降低呈指数下降趋势,温度每降低8.58 K,暗计数率减小一半,当温度从274 K降低到192 K时,该雪崩二极管的暗计数率从13900 Hz减小到了14 Hz。将工作温度为260 K,暗计数率为58 Hz的单光子雪崩二极管冷却到192 K,并且调整二极管两端的偏置电压,使其在波长为852 nm时的探测效率为50%,暗计数率降为0.064 Hz,后脉冲概率为6.7%,单光子探测器的性能得到显著提高。这种超低暗计数率单光子探测器在量子通讯、弱光探测等领域具有广阔的应用前景。

In this work,the temperature characteristics of a single-photon avalanche diode working in Geiger mode are studied.The experimental results show that the avalanche voltage of the avalanche diode linearly decreases with the decrease in temperature and the voltage temperature coefficient is 0.42 V/K.When the avalanche diode works at an avalanche voltage of more than 13 V,the dark count rate decreases exponentially with the decrease in temperature.In addition,the dark count rate decreases by half for each 8.58 K decrease in temperature.Furthermore,when the temperature drops from 274 K to 192 K,the dark count rate of the avalanche diode also decreases from 13900 Hz to 14 Hz.The single-photon avalanche diode with an operating temperature of 260 K and a dark count rate of 58 Hz is cooled to 192 K.The bias voltage at both ends of the diode is adjusted to ensure that the dark count rate is reduced to 0.064 Hz and the after-pulse probability is 6.7%when the detection efficiency is 50%at wavelength of 852 nm.Thus,the performance of the single-photon detector is significantly improved.Moreover,the single-photon detector with an ultra-low dark count rate has significant applications in quantum communication and weak light detection.