Recent advances in avalanche photodiodes

This paper will review recent advances in linear- and Geiger mode avalanche photodiodes (APDs). The focus for linear-mode devices will be materials and structural modifications to the conventional InP/InGaAs APD that have enabled reduced excess noise and enhanced gain-bandwidth products. The discussion of Geiger mode APDs will cover the basic operation and principal performance parameters with emphasis on techniques to reduce afterpulsing.