Acoustooptic Resonance in Deep-Etched GaAs–AlGaAs Electrooptic Modulators

Deep-etched GaAs-AlGaAs waveguide modulators are shown to generate acoustic waves that can cause elastooptic anomalies in the modulator response. The theory of acoustooptic interactions in linear electrooptic modulators is described and a one-dimensional (1-D) approximation of a deep-etched GaAs-AlGaAs waveguide modulator is developed. The 1-D theory is shown to predict the acoustooptic resonance phenomena that is seen in experimental devices.