Research Reveals How Staircase Photodetector Amplifies Signals with Low Noisemkw3a@virginia.edu
Adam Dadey, a Ph.D. student of electrical engineering at the University of Virginia School of Engineering and Applied Science, earned the top student paper award at the 2021 IEEE Photonics Conference for his contributions to three- and five-step staircase avalanche photodiodes.
Dadey fabricates and then characterizes the properties and performance of avalanche photodiodes for imaging systems and related applications, alongside members of the photonic devices group led by Joe Campbell, Lucien Carr III professor of electrical and computer engineering.
Dadey’s paper, Cryogenic Noise of Staircase Avalanche Photodiodes, reports on the group’s advances in photodetectors that perform well in the visible and near-infrared light spectrum. These so-called staircase photodetectors rely on semiconductor-based avalanche photodiodes, a technology for which Campbell has led pioneering, standard-setting research.
The team’s avalanche photodiode achieves high efficiencies or gain — meaning that a single photon creates many electrons — with the lowest amplifying noise ever reported. Dadey’s research has helped the team pinpoint and control this process, removing randomness and reducing noise.
Campbell’s group, in collaboration with Seth R. Bank, Cullen Trust Professor at UT-Austin, is the first to successfully demonstrate this novel detector that was first proposed 35 years ago but never before realized.
“This is exciting work that has the potential to be a game changer for applications as diverse as optical communication networks, next-generation imaging systems and ‘vision’ for autonomous vehicles,” Campbell said.