Wave-front engineering by Huygens-Fresnel principle for nonlinear optical interactions in domain engineered structures

TL;DR

This paper introduces a wave-front engineering method based on the Huygens-Fresnel principle for nonlinear optical interactions, enabling localized quasi-phase matching and multifunctional device integration.

Contribution

It develops a general theory for domain engineering in nonlinear optics, introducing local quasi-phase matching and a compact scheme for multiple optical functions.

Findings

Experimental results confirm the focal effect of second-harmonic waves.

The scheme achieves simultaneous generation, focusing, and beam splitting.

The approach enhances multifunctionality and integration in nonlinear photonic devices.

Abstract

The wave-front engineering for nonlinear optical interactions was discussed. Using Huygens-Fresnel principle we developed a general theory and technique for domain engineering with conventional quasi-phase-matching structures being the special cases. By Fourier analysis we put forward the concept of local quasi-phase matching, which suggests that the quasi-phase matching is fulfilled only locally not globally. Experiments on focal effect of second-harmonic wave agreed well with the theoretical prediction. The proposed scheme combines three optical functions: generation, focusing and beam splitting of second-harmonic wave, thus making the device more compact. Further the proposed scheme can be used to perform the integration of multi-functional optical properties in nonlinear photonics, as well as expand the use of nonlinear optical devices.