Fiber amps and lasers get down to earth

Practical optical fiber devices, particularly erbium-doped fiber amplifiers (EDFAs), are poised to tap the tremendous bandwidth of optical fibers in next-generation lightwave transmission systems, while enhancing network flexibility and reliability. Optical fiber amplifiers have come a long way since the first demonstration of a neodymium-doped type by Snitzer and Koester in 1964. It was not until the mid-1980s, however, that researchers began to revitalize and extend the field of rare-earth doped fiber devices by combining the technologies of low-loss silica optical fibers, rare-earth doped lasers, and semiconductor pump sources. Later this year, they will be practically applied in a big way