Physical Society Colloquium

Nonlinear Photonics in III-V Semiconductors

Ksenia Dolgaleva

School of Electrical Engineering and Computer Science
University of Ottawa

Rapid development of nanofabrication has stimulated the growth of the field of nonlinear photonics. Nonlinear photonic devices are finding their applications in more and more areas, including (but not limited to) classical and quantum communications, sensors, nonlinear spectroscopy and other. The material platforms used for nonlinear photonics on-a-chip range from transparent dielectrics with a relatively weak nonlinearity to semiconductor materials with strong nonlinear interactions.

Among the materials for nonlinear photonics on-a-chip, group III-V semiconductors stand out due to their attractive optical properties such as high refractive index and nonlinear coefficients. Furthermore, most III-V semiconductors exhibit direct bandgap and light-emitting properties. In combination with the capability for tailoring the photonic bandgap energy and optical properties available in the ternary and quaternary III-V semiconductors, a monolithic integration of active and passive on-chip optical components essentially on the same material platform is possible. Moreover, most III-V semiconductors lack the centre of the inversion symmetry exhibiting strong second-order nonlinear optical coefficients. These properties make group III-V semiconductors attractive for on-chip nonlinear photonics applications.

In this presentation, I will overview the field of III-V nonlinear photonic devices with the emphasis on our research group contributions. I will talk about two particular III-V semiconductor compounds, aluminum gallium arsenide (AlGaAs) and indium phosphate (InP), that our research group specializes in. Specifically, I will describe existing waveguide geometries, fabrication approaches and challenges, and nonlinear optical performance of various wavegudes and devices based on the aforementioned III-V semiconductor platforms.