Dependence of the sensitivity of intracavity laser spectroscopy on generation parameters

The dependence of the sensitivity of intra-cavity laser spectroscopy (ILS) at the transition stage of generation on the pumping power and spectral width has been investigated experimentally. The time interval of linear growth of the sensitivity is shown to be limited and determined by the excess of the pumping power over the threshold. The combination of physical parameters of the system which determines the value of the effect is found. Possible mechanisms of the phenomenon are discussed. Insufficiency of the generally accepted description of a multimode laser in ILS within the frames of rate equations and the necessity of the inclusion of parametric processes are pointed out.