Variations of the confining potential of doped AlGaAs/GaAs Quantum Wells with the photon energy of excitation.

A series of doped GaAs/AlGaAs single quantum well samples has been investigated using photoluminescence (PL) and PL excitation (PLE) spectroscopy. The samples are of 100 A well width and are doped in the central 50 A with Si in the range 5 x 10 high 8 to 2 x 10 high 12 cm high -2. A strong dependence of the optical spectra on the photon energy of excitation is observed. This dependence is interpreted in terms of a charge transfer process between the AlGaAs barrier and the quantum well (QW), which determines the charge and potential distribution in the QW.