Intersubband transition spectroscopy of GaAs/AlGaAs quantum well superlattice

The physics and application of the intersubband transitions in GaAs/AlGaAs quantum well superlattice structures have been under intense investigation in recent years. In this report, theoretical design and experiment of three GaAs/AlGaAs quantum well superlattice samples are given in detail. The samples are grown by MBE technique on semi-insulating GaAs substrate. The three samples have different growth parameters and therefore different energy band structures. The transitions have bound to bound and bound to continuum states. Fourier Transform Infrared (FTIR) spectra and the infrared photoelectron tunneling (IPET) spectra are measured and the results agree well with each other and with the calculations.