Determination of the effective stimulated emission cross section for a neodymium laser with a selective resonator

A method is developed for determining the stimulated emission cross section, sigma(eff), in a neodymium laser with a selective resonator. It is shown that kinetic equations for an inhomogeneously broadened line can be simplified considerably as a result of the external variation of the gain and of the selective properties of a Fabry-Perot interferometer inserted in the resonator. An analytic relationship between sigma(eff) and the experimentally determined parameters is obtained using the solutions of these equations. An advantage of this method is that it is possible to probe the spectral line of the active medium by tuning the central frequency of the selective resonator, as well as the lack of indeterminacy in finding sigma(eff).