Nonlinear optics of randomly structured strontium tetraborate

Random quasi phase matching (RQPM) in nonlinear photonic crystal was investigated for the conversion of both narrowband and broadband fundamental radiation. Angular dependence of RQPM effect was experimentally studied, and agreement with a simple theoretical model was demonstrated. The enhancement factor due to RQPM is shown to be fairly predictable on the basis of known NPC geometry. The spectral dependence of RQPM effect was calculated for a number of NPC structures that are typically produced in SBO. Main features of these dependences will be discussed. The relation between angular and spectral dependences is analysed.