YTTERBIUM-DOPED SILICA FIBER LASERS - VERSATILE SOURCES FOR THE 1-1.2MU-M REGION

Ytterbium-doped silica fibers exhibit very broad absorption and emissi on bands, from similar to 800 nm to similar to 1064 nm for absorption and similar to 970 nm to similar to 1200 nm for emission, The simplici ty of the level structure provides freedom from unwanted processes suc h as excited state absorption, multiphonon nonradiative decay, and con centration quenching, These fiber lasers therefore offer a very effici ent and convenient means of wavelength conversion from a wide variety of pump lasers, including AlGaAs and InGaAs diodes and Nd:YAG lasers, Efficient operation with narrow linewidth at any wavelength in the emi ssion range can be conveniently achieved using fiber gratings, A wide range of application for these sources can be anticipated, In this pap er, the capabilities of this versatile source are reviewed. Analytical procedures and numerical data are presented to enable design choices to be made for the wide range of operating conditions.