Generation of non-Gaussian flat laser beams

The use of non-Gaussian flat laser beams is currently under study to reduce the thermoelastic noise in the advanced gravitational wave interferometers. In this work we present a system based on two deformable mirrors to transform a Gaussian beam in a non-Gaussian flat beam. We use an approximated representation of flat beam based on the usual Hermite-Gaussian modes which is particularly useful when the flat beam is generated by using deformable mirrors. This system can be used either for flat beams generation or for beam matching in the mexican-hat mirrors Fabry–Perot cavities proposed for next generation of gravitational wave interferometers.