Nonlinear conversion efficiency of random quasi-phase matching in polycrystal influenced by grain morphological properties

A Monte-Carlo simulation was performed on the efficiency of random quasi-phase matching (RQPM) nonlinear optical frequency conversion in polycrystalline materials to show the detailed influence of the statistical grain morphology properties. The simulation took second harmonic generation (SHG) for example and considered the parameters of beam size, beam distribution, fundamental wavelength variation, polycrystalline average grain size (mean), standard deviation (Std), etc. The results and conclusions could enrich the theory of RQPM and provide guidance for polycrystalline material processing and sample selection for specific nonlinear-optical experiments.