Abstract
The afterpulse effect is one of the major bottlenecks limiting the performances of InGaAs/InP single-photon avalanche photodiodes (SPADs) for high-speed operation. In this paper, we present a practical and easy way to implement an afterpulse suppression scheme. Using an analog integrator circuit to discriminate small avalanche signals, we reduced drastically the afterpulse noise of the detector. At a repetition frequency of 25 MHz, the overall afterpulse probability is 1.48% with a detection efficiency of 15.6% and a dark count probability of 1.3×10-5. In addition, the detector features a maximum count rate of 25 MHz.