Polarization-insensitive electroabsorption by use of quantum well interdiffusion

Abstract

The use of interdiffusion in different as-grown square QW structures to produce a paraboliclike potential profile to achieve polarization insensitivity of electroabsorptive modulation was studied. These QW's were optimized to achieve three equivalent parabolic AlxGa1-xAs/GaAs QW's of various x from 0.3 to 0.4. Two criteria were proposed for the successful achievement of paraboliclike DFQWs: the first is to start with a narrower as-grown rectangular well width than that of the targeted PQW whereas the second is to use a less extensive interdiffusion. The chronological procedures to obtain polarization-insensitive on-state and off-state electroabsorptive modulation were also proposed.