Study of the Michelson resonator dispersion of an absorption-cell multimode laser with a strong intermode coupling

Abstract

Summary form only given. The goal of this paper is a theoretical study of the generation modes of a wide-band multimode laser with a Michelson resonator and an absorption cell with atomic gases in one of the arms, as well as an interpretation of the experimental results on the basis of this analysis. Having a strong nonlinear coupling between the Michelson resonator modes through an atomic absorbing medium inside the resonator (in one of the arms), it is possible to have the following generation modes: (a). Stabilization of the laser frequency in the absorption line center due to the supernarrow dispersion resonance at the average frequency; (b). Generation mode where the difference in mode beat frequency difference gives a narrow frequency resonance with a field narrower than the natural width; (c). Generation mode where it is possible to split the central mode; one of the frequencies tracing the central mode frequency of an empty resonator. The calculations explain a number of effects: absorption line splitting, presence of supernarrow resonances at intermode beat subharmonics, emission concentration effect near the absorption line. These effects can be used to work out new techniques of intraresonant spectroscopy having a high sensitivity.