The effect of complex band structure and non-parabolicity on sub-bands of GaAs-AlxGa1-xAs heterostructures: band offset

Abstract

The authors use the usual effective mass envelope function approach to study the sub-band levels of GaAs-Al_xGa_1-xAs quantum well structures by considering the complex band structures and the non-parabolicity of bulk component materials. The energy differences of sublevels in rectangular single-quantum-well structures are calculated with adjustable well width and band offset parameter Q_c (= Delta E_c/ Delta E_g). Comparison of the results with experimental data suggests that Q_c is around 0.65. Also, they present a feasible method for determining Q_c independently of other input parameters (such as the effective masses, the well width and the Al concentration) by the field-induced Stark effect on sublevels of electrons and holes or exciton peaks in quasi-parabolic multiple-quantum-well structures.