Thermo-optical distortions in second-harmonic generation in nonlinear crystals

An analysis is made of the elasto-optical contribution to changes in the refractive index in the course of second-harmonic generation in crystalline samples which are in the form of circular cylinders and have a steady-state parabolic temperature field. The associated changes in the wave mismatch and in the intrinsic polarisations of the interacting waves are also considered.