Systematic afterpulsing-estimation algorithms for gated avalanche photodiodes

TL;DR

This paper introduces efficient algorithms for estimating and mitigating afterpulsing in gated InGaAs avalanche photodiodes, enabling high-efficiency detection even near saturation and in real-time or post-processing contexts.

Contribution

The paper presents novel algorithms for accurately estimating afterpulsing effects in gated APDs, facilitating improved signal extraction and high-efficiency operation.

Findings

Algorithms work near saturation levels

Effective in real-time and post-processing

Compatible with high detection efficiencies

Abstract

We present a method designed to efficiently extract optical signals from InGaAs avalanche photodiodes (APDs) operated in gated mode. In particular, our method permits an estimation of the fraction of counts which actually results from the signal being measured, as opposed to being produced by noise mechanisms, specifically by afterpulsing. Our method in principle allows the use of InGaAs APDs at high detection efficiencies, with the full operation bandwidth, either with or without resorting to the application of a dead time. As we show below, our method can be used in configurations where afterpulsing exceeds the genuine signal by orders of magnitude, even near saturation. The algorithms which we have developed are suitable to be used either in real-time processing of raw detection probabilities or in post-processing applications, after a calibration step has been performed. The algorithms which we propose here can complement technologies designed for the reduction of afterpulsing.