Photonic integrated erbium doped amplifiers reach commercial performance

Erbium-doped fiber amplifiers (EDFAs) are devices that can provide gain to the optical signal power in optical fibers. They are often used in long-distance communication fiber optic cables and fiber-based lasers. Invented in the 1980s, EDFAs have profoundly impacted our information society enabling signals to be routed across the Atlantic and replacing electrical repeaters.