Affiliation:
1. University of Science and Technology of China
2. Chinese Academy of Sciences
Abstract
A photodetector signal-to-noise ratio (SNR) over 1000 is one of the prerequisites to realizing the correlated photon radiometric benchmark with a relative standard uncertainty of 0.3% (k=1). To improve the SNR for low-photon flux detection, a switched integration amplifier (SIA) is designed to achieve a noise equivalent current of a fA level. A wide spectrum and low-photon flux measurement facility are built to evaluate the SNR at a photon rate of 108s−1 within the spectral range of 350–1000 nm. SNRs of the SIA-based Si photodetector are shown to be greater than 1000 at representative wavelengths.
Funder
National Key Research and Development Program of China
Subject
Atomic and Molecular Physics, and Optics,Engineering (miscellaneous),Electrical and Electronic Engineering