New design of InGaAs-InGaAlAs MQW electroabsorption modulator for high-speed all-optical wavelength conversion

We have optimized the structure of InGaAlAs multiple quantum-well electroabsorption modulators for all-optical signal processing. As wavelength conversion is a key function for all-optical telecommunication network, we have based our optimization upon the main parameters of this function, namely, polarization insensitivity, exciton saturation, and photogenerated carrier sweep-out time. Four samples have been studied with different well tensile strain and barrier height. We find low polarization dependence over a range of applied bias. Less than 10-ps absorption-saturation recovery time at lower biases and smaller saturation power than in the literature are reported.