Dependence of Functional Parameters of Sine-Gated InGaAs/InP Single-Photon Avalanche Diodes on the Gating Parameters

In this paper, we investigateda self-developed sine wave gated single-photon detector (SPD) for 1550 nm wavelength primary for quantum key distribution (QKD) usage. We studied the influence of DC bias voltage and AC gate amplitude on the SPD’s functional parameters and presented a simple and effective algorithm for its optimization. Such optimization showed practical benefits while SPD was set up on the QKD device. We admitted that the dark count rate decreases with an increase in gating voltage with fixed photon detection efficiency. We observed the charge persistence effect in sine-gated SPDs, which previously had been observed only at square-pulses gated SPDs, and showed that this effect is limiting for infinity increasing gate amplitude.