Avalanche Photodiodes Operate At GHz Speeds

A pair of avalanche photodiodes (APDs) are designed to operate at 2.5 and 10 Gb/s speeds for use in long-haul and metropolitan area network (MAN) optical communication systems. When the APD detects incoming laser light, the photodiode conducts and amplifies the resulting current by avalanching, which increases receiver sensitivity. The APDs incorporate an avalanche layer fabricated with indium aluminum arsenide (InAlAs) rather than the conventional indium phosphide (InP), resulting in improved sensitivity and reduced noise. SPECTROLAB INC., Sylmar, CA. (818) 898-7540.