Laser frequency doubling in the nonlinear optical crystals with disordered domain structure

摘要

We develop theory of the second harmonic generation (SHG) in nonlinear optical crystals with random domain structure. The theory takes into account fluctuations of phase mismatch and nonlinear wave coupling coefficient. Dependence of SH intensity on interaction length and fundamental radiation intensity is examined. The latter may differ from quadratic law in the region of small nonlinear conversion efficiencies.