High-gain and high-efficiency diode laser pumped fiber amplifier at 1.56 mu m

Abstract
Gain of an erbium-doped amplifier was optimized for operation at 1.56 mu m, resulting in gains of up to 20 dB and slope efficiencies of 0.66 dB/mW. The amplifier is plug compatible with existing fiber networks. The gains of up to 20 dB were achieved using 1.48-1.49 mu m laser diode pump sources with powers of 30 mW launched into the input of the system. The erbium-doped fiber used had an Er/sup 3+/ concentration of roughly 30 p.p.m. in a GeO/sub 2/-Al/sub 2/O/sub 3/SiO/sub 2/ host, and a core diameter of 7.0 mu m.