REVIEW OF RARE-EARTH DOPED FIBER LASERS AND AMPLIFIERS

Recent developments in rare earth doped fiber lasers and amplifiers are reviewed. Fiber lasers have been made to operate at a variety of wavelengths, including the important 1.3 μm, 1.55 μm and the 2 to 3 μm regions in the infrared. The spectra of the rare earth ions and the nature of the host materials that make such lasing wavelengths possible are discussed. Methods for the manufacture of rare earth doped fibers are reviewed. A number of cavity designs for fiber lasers have been demonstrated, which have facilitated low loss coupling to transmission fibers, single longitudinal mode operation, Q-switching and mode locking. The performance of these systems is described. The operation of rare earth doped fiber amplifiers is also discussed.