Efficient Type II Second Harmonic Generation in an Indium Gallium Phosphide on insulator wire waveguide aligned with a crystallographic axis

TL;DR

This paper demonstrates both theoretically and experimentally that type II second harmonic generation in indium gallium phosphide wire waveguides can achieve high efficiency by optimizing propagation direction and leveraging longitudinal fields, surpassing type I efficiency.

Contribution

It introduces a novel approach to enhance second harmonic generation efficiency in III-V-on-insulator waveguides through propagation direction control and field component utilization.

Findings

Achieved 12%/W conversion efficiency experimentally.

Theoretical prediction of higher maximum conversion than type I.

Propagation direction significantly affects conversion efficiency.

Abstract

We theoretically and experimentally investigate type II second harmonic generation in III-V-on-insulator wire waveguides. We show that the propagation direction plays a crucial role and that longitudinal field components can be leveraged for robust and efficient conversion. We predict that the maximum theoretical conversion is larger than that of type I second harmonic generation for similar waveguide dimensions and reach an experimental conversion efficiency of 12 %/W, limited by the propagation loss.