Kinetics of the radiation spectrum of a multimode laser with a rapidly relaxing active medium

The spectral kinetics of a multimode laser with a rapidly relaxing active medium is analyzed under the most general assumptions concerning the dispersion properties of the cavity, the time behavior of pumping and losses, and the position and dimensions of the active medium. An analysis of the balance equations for the nonstationary stage was used to determine the form of the photon mode distribution function and to reduce the problem of spectrum evolution to the analysis of reference-mode dynamics. A number of particular cases of practical importance are examined, including a small excess over the threshold and the specific dispersion characteristics of the cavity.