Energy levels and electron wave functions in semiconductor quantum wells having superlattice alloylike material (0.9 nm GaAs/0.9 nm AlGaAs) as barrier layers

Abstract

Energy levels and wave functions of carriers are studied both experimentally and theoretically in 4 nm GaAs quantum wells (QW’s), for the case when barriers are formed with alternating layers of 0.9 nm GaAs/0.9 nm AlxGa1−xAs (x=0.39). The photoluminescence spectra of the QW’s are studied at 77 K and are found nearly equivalent to that of conventional QW’s having alloy barriers with Al content of 0.26, which is much higher than the averaged alloy composition (∼0.2). The modified Kronig–Penney analysis is found effective in predicting the observed energy and has clarified a feature of enhanced penetration of wave function into the novel barrier layer.