Turbulent structure of the active medium of a fast-flow CO{sub 2} laser

The characteristics of turbulent pulsations of the gas density and velocity and the structural characteristic of fluctuations of the refractive index C{sub n}{sup 2} in the gaseous-mixture flow of a fast-axial-flow CO{sub 2} laser are determined using optical diagnostic methods: the luminescence, interferometry, and degenerate four-wave mixing techniques. The influence of a gas discharge and lasing on turbulent small-scale optical inhomogeneities of the active medium is investigated. It is shown that, in the presence of a gas discharge and laser oscillation, the inhomogeneities appreciably increase due to nonlinear effects of a local heat release in the thermodynamically nonequilibrium turbulent gaseous medium. (special issue devoted to the memory of academician a m prokhorov)