E(1) TRANSITION IN (113)-ORIENTED GAAS ALAS MULTIPLE-QUANTUM WELLS - CONFINEMENT EFFECTS AND OPTICAL ANISOTROPY/

A study about the E(1)-like transition in (113)-oriented GaAs/A1As mul tiple quantum wells is presented. The electroreflectance, which was pe rformed using light polarized along the [33(2) over bar] and [<(1)over bar 10>] in-plane perpendicular directions, was the utilized experime ntal technique. We have found that the considered transition shifts to wards higher energies as the well thickness decreases and takes place at different values of energy depending on the light polarization, bei ng less energetic in the [33(2) over bar] electroreflectance spectra t han in the [<(1)over bar 10>] electroreflectance spectra. The observed energy shift can be explained in terms of quantum confinement effects while the observed in-plane optical anisotropy is due to the splittin g of the GaAs E(1) transition induced by the confined potential charac teristic of the considered nanostructures.