Normalized reflection spectra in InxGa1-xAs/GaAs strained quantum wells: Structure and electronic properties

A systematic study of GaAs/InxGa1-xAs single quantum wells is performed in two sets of samples with different alloy concentrations (x = 9% and 18.5%) and well thicknesses ranging from 15 to 250 Å. These samples are grown by an MBE facility and characterized by "normalized reflection spectroscopy". Normalized reflection spectroscopy is able to study exciton properties and also to take under control indium diffusion at the interfaces of the samples. Finally, the range of thicknesses where asymmetric QWs show a large asymmetry in the exciton envelope function is pointed out.