Aluminum gallium nitride directional-coupler switch

This dissertation describes an attempt to develop, including material processing, a zero-gap directional coupler using the AlGaN material system in an n-i-n configuration that was grown by MBE. This work compiles the optical and electro-optical properties and models the behavior of AlGaN integrated optic waveguides. The switches are based on the zero-gap electro-optic directional coupler. The models are compared with the experimental results that were obtained. The models used were the Marcatili and the beam propagation method. Models for predicting the index of refraction of AlGaN versus Al concentration are treated. An advantage of the AlGaN integrated optic waveguides and switches is the potential to work at wavelengths from IR to the blue region. AlGaN has the potential to work at high temperatures and in harsh environments. The wavelength chosen for this work is 632.8 rim from a HeNe laser.; The results show that an electro-optic switch is viable in the AlGaN system. Material maturity is necessary to improve performance. The models chosen were shown to be inaccurate by themselves. Together they are a viable source for the development of a directional coupler surrounded by air.