Spectroscopy studies by reflectance and photoluminescence on shallow quantum wells AlxGa1−xAs/GaAs types

We report an experimental study by photoluminescence (PL) and reflectivity on shallow quantum wells of Ga1−xAlxAs/GaAs type performed at 10 K and varying aluminium concentration from 1.5% to 4.5%. We present an approach to the investigation of the reflectivity line shape. The calculations of the reflectance line shapes using the classical model of linear dispersion show good agreement with the experimental spectra, in particular, the two types of the line shapes: “dip” for the quantum well and “peak” for the barrier exciton.