Investigation of an amplifier with a composite active element and a stimulated Brillouin scattering mirror

An experimental study was made of the spatial characteristics of a laser with a telescopic amplifier, a composite neodymium glass active element, and a stimulated Brillouin scattering (STBS) mirror. It was found that in an amplifier with a composite active element and with wavefront reversal, as a result of STBS in focused beams in the presence of aberrations, causing an overlap of the focusing zones of the individual beams, there was no need to ensure exact convergence of the beams. The wavefront phase set by the master laser was conserved and the nature of the angular distribution of the radiation was governed by the shape of the composite aperture and by the quality of wavefront reversal realized in the selected scheme.