NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Gigahertz-gated InGaAs SPAD system with avalanche charge sensitivity approaching the fundamental limit
Published
Author(s)
Alessandro Restelli, Joshua C. Bienfang, Alan L. Migdall
Abstract
We present an InGaAs/InP single-photon detection system operating at 1.25 GHz with detection efficiency above 50 % and per-gate afterpulse probability, measured 24.8 ns after an avalanche, below 0.2 %. The high efficiency and low afterpulse probabilities we observe are achieved with an avalanche discrimination system whose threshold for detection approaches the fundamental limit imposed by Johnson noise on a 50 Ohm load; we measure the threshold to be less than 8 fC. We discuss the design and performance of our approach, and tradeoffs between detection efficiency, afterpulse probability, and maximum count rate.
Restelli, A.
, Bienfang, J.
and Migdall, A.
(2013),
Gigahertz-gated InGaAs SPAD system with avalanche charge sensitivity approaching the fundamental limit, SPIE Defense Security Sensing, Baltimore, MD, [online], https://doi.org/10.1117/12.2016087
(Accessed October 1, 2025)