Fiber amplifiers are optical amplifiers with doped fibers as gain media. Erbium-doped and ytterbium-doped fiber amplifiers are the most important types. This category are ytterbium-doped fiber amplifiers , also named YDFA .

EDFA operates in the wavelength region from 1530 nm to 1565 nm with semiconductor laser pump wavelengths of 980 nm and 1480 nm. YDFA operates in a broad wavelength range from 975 nm to 1200 nm with pump wavelengths of 910 nm and 975 nm.