High-sensitivity photon-counting communications using Geiger-mode avalanche photodiodes

Recent advances in Geiger-mode avalanche photodiode technology have made these devices practical for high-sensitivity photon-counting optical communications. We report on recent experiments using 1.06 /spl mu/m and 1.55 /spl mu/m Geiger-mode avalanche photodiodes to demonstrate optical communications with multiple bits per detected photon.