High extinction ratio GaAs/AlGaAs electroabsorption modulators integrated with passive waveguides using impurity-free vacancy diffusion

Electroabsorption optical modulators integrated with passive waveguides have been fabricated on GaAs/AlGaAs multiquantum well material using the impurity-free vacancy diffusion technique with SrF2 and SiO2 capping layers. At a wavelength of 861.6 nm, devices with a 400 µm long modulator section showed ON/OFF ratios greater than 35 dB for a reverse bias voltage of 3 V.