LENGTH OPTIMIZATION OF SINGLE-MODE RARE-EARTH-DOPED WAVE-GUIDES USINGSATURATED ABSORPTION

Absorption saturation was demonstrated to provide a high, uniform popu lation inversion over a length of waveguide longer than the material a bsorption length, The small signal gain was measured experimentally in single-mode waveguides, made by silver ion exchange, on a commerciall y available neodymium doped glass, The ratio of the excited states was calculated as a function of waveguide length and was shown to be a co nvenient criteria to determine the optimum device length.