Analysis of torque mounting configuration for nonlinear optics with large aperture

•A torque mounting configuration with the external load bringing in the forced torque was proposed.•Two kinds of torque generated in the torque mounting configuration were identified.•Four design parameters were identified and their effects were studied.•The design parameters effects on the distortion and stress were analyzed and discussed from the view of torque.•The distortion and stress effects on the phase mismatch and second harmonic generation efficiency were discussed.

Motivated by the need of decreasing the gravitational distortion and stress of the nonlinear optics with large aperture, as well as increasing the second harmonic generation (SHG) efficiency, a torque mounting configuration was proposed, where the external load brought about the torque to mitigate the distortion and stress. The distortion and stress were calculated by using the Finite Element Method (FEM), and discussed from the view of torque. The effects of the design parameters, namely the external load, loading width, shim plate location and shim plate width, were studied; the changing trends of the distortion and stress with these varying parameters were analyzed. Furthermore, the phase mismatches induced by the distortion and stress were calculated; finally, the SHG efficiency was solved considering the phase mismatch.