Abstract Optical parametric amplification (OPA) is a nonlinear process through which low-power input wave amplified by extracting energy from an interaction medium that energized high-intensity pump wave. For significant of wave, sufficiently long required, usually on the order few centimeters. Therefore, in small scale, OPA considered unfeasible, and this prevents it being employed micro nanos...

We investigate interesting symmetry properties verified by the down-converted beams produced in optical parametric amplification with structured light. show that Poincar\'e sphere symmetry, previously demonstrated for first-order spatial modes, translates to a multiple structure higher orders. Each one of these spheres is associated two-dimensional subspace defined different value orbital angul...