Characteristics of unstable resonators with field distortions in their components. II. Spherical mirrors

The fast Fourier transformation method is used to obtain a numerical solution of the integral equations describing an unstable confocal resonator with spherical mirrors. A study is made of the field distortions characteristic of the operation of a resonator filled with a fast-flowing active medium, such as asymmetric distortions of the mirror surfaces simulating thermal deformation, small-scale random phase inhomogeneities, and a phase inhomogeneity resulting from the formation of compression and expansion waves in a supersonic stream. Calculations are made of the situation in the case of lasing in a fast-flowing stream consisting of a mixture of carbon dioxide, nitrogen, and water vapor.