Electro-optic and acousto-optic modulators using Stark effect in multiple quantum well structures

Abstract

Enhanced changes in absorption, index of refraction and birefringence have been observed in InGaAs-GaAs multiple quantum well structures operating in the 980-1000 nm range. The changes in optical parameters are used to develop electro-optic as well as acousto-optic modulators. Preliminary work on heterostructure acoustic charge transport (HACT) to address an array of high contrast pixels is presented. HACT addressing is shown to result in about 3×n interconnects in place of n×n needed in conventional row/column select techniques. This is relevant to the implementation of compact, high-contrast spatial light modulators at clock rates approaching 1 GHz for optical computing and image processing applications. Results on modulators using surface acoustic wave (SAW) induced Stark effect, and switching and modulation in novel structures consisting of electro-optic Bragg gratings (induced by quadratic index changes due to Stark effect) are reported