3D-PSTD for modelling second harmonic generation in periodically poled lithium niobate ridge-type waveguides

TL;DR

This paper introduces a 3D pseudo-spectral time domain method to accurately model second harmonic generation in lithium niobate ridge waveguides, analyzing efficiency and multimode effects based on geometry and poling patterns.

Contribution

It presents a novel application of the tri-dimensional pseudo-spectral time domain algorithm for nonlinear optical modeling in complex waveguide structures.

Findings

High conversion efficiency predicted for specific geometries.

Multimode effects significantly influence the nonlinear process.

Periodic poling enhances second harmonic generation performance.

Abstract

We report an application of the tri-dimensional pseudo-spectral time domain algorithm, that solves with accuracy the nonlinear Maxwell's equations, to predict second harmonic generation in lithium niobate ridge-type waveguides with high index contrast. Characteristics of the nonlinear process such as conversion efficiency as well as impact of the multimode character of the waveguide are investigated as a function of the waveguide geometry in uniformly and periodically poled medium.