Directional coupler switch in molecular-beam epitaxy GaAs

Abstract
An 8‐mm‐long rib waveguide directional coupler has been made from a n (1×1016 cm−3) GaAs layer grown by molecular‐beam epitaxy. By reverse biasing the ’’stepped Δβ’’ Schottky electrodes with less than 30 V, more than 17 dB power isolation has been achieved at 1.06 μm for both switching states. Improvements are expected with the progress in layers morphology and doping level. This is a new step towards the feasibility of optoelectronic devices by a growth technique which is very attractive for GaAs integrated circuits.