Elliptically polarized sum-frequency generation by total-internal-reflection-based optical rotation quasi-phase-matching technique.

Abstract

This work demonstrates the elliptically polarized radiation of sum-frequency generation by the total-internal-reflection-based optical rotation quasi-phase-matching technique that allows polarization rotation in the presence of an external electric field across a rectangular-shaped, Y2O3-coated, MgO-doped LiNbO3 crystal. This thin film is employed to control the phase shifts generated by p- and s-polarized light propagation at each bounce point of the slab-film interface. The computer-aided simulation yielded a high conversion efficiency of 7.5%/W/cm, reflecting the combined field impact of the optical rotation quasi-phase-matching and fractional quasi-phase-matching approaches. Moreover, the conversion yielding limiting factors such as absorption, surface roughness, and the interference effect of the nonlinear law of reflection have also been included to simulate the generation of a 770 nm wavelength. A comparative assessment of the generated linearly and elliptically polarized radiations has also been addressed.