Analysis of a InGaAs/InP single photon detector at 1550 nm

摘要

A new type of single-photon detector is introduced and its related properties characterized. The single-photon detector operating in the Geiger mode uses a new type of cooling system to moderate temperature, which can make the temperature drop to -65 °C. Besides, the single-photon detector adopts a hold-off time modulation feedback control circuit to decrease the afterpulsing effects and the gate pulse is coupled to the avalanche diode through capacitance. In addition, a suitable delay and comparator with latch function circuit are used to detect avalanche signals. Experimental conditions are that the clock frequency is 10 MHz, refrigeration temperature is -65 °C, and the width of control pulse is 5 ns. The experimental results indicate that quantum efficiency is about 20.42% and the dark count rate is about 5 × 10 ~(-6) ns~(-1) with signal-to-noise ratio 27 dB at the optimum operation point of this detector. The designed single-photon detector achieves a tradeoff between lower dark count rates and high quantum efficiency.