Influence of a nonlinear absorber on the radiation parameters of a laser with periodically varying optical length

Relaxation processes are allowed for in an analysis of the influence of a gaseous nonlinear absorber on oscillations of a single-mode He–Ne/CH₄ laser when its resonator length is varied periodically at a frequency Ω. Investigations are made of the frequency and amplitude modulation parameters as a function of Ω and of the tuning of the average oscillation frequency within the methane line. It is shown, in particular, that the dependence of the radiation frequency deviation on Ω changes substantially when the average laser frequency is detuned from the center of the methane transition by a value appreciably greater than its homogeneous width.