High speed single photon detection in the near-infrared

TL;DR

This paper demonstrates high-speed single photon detection in the near-infrared using InGaAs APDs with a self-differencing technique, achieving GHz gating frequencies, low afterpulse noise, and high detection efficiency.

Contribution

The study introduces a method to operate InGaAs APDs beyond 1 GHz gating frequency with reduced afterpulse noise, enabling faster NIR photon detection.

Findings

Gating frequencies beyond 1 GHz achieved

Detection efficiency of 10.8% at 1.25 GHz

Afterpulse probability reduced to 6.16%

Abstract

InGaAs avalanche photodiodes (APDs) are convenient for single photon detection in the near-infrared (NIR) including the fibre communication bands (1.31/1.55 $\mu$m). However, to suppress afterpulse noise due to trapped avalanche charge, they must be gated with MHz repetition frequencies, thereby severely limiting the count rate in NIR applications. Here we show gating frequencies for InGaAs-APDs well beyond 1 GHz. Using a self-differencing technique to sense much weaker avalanches, we reduce drastically afterpulse noise. At 1.25 GHz, we obtain a detection efficiency of 10.8% with an afterpulse probability of 6.16%. In addition, the detector features low jitter (55 ps) and a count rate of 100 MHz.