Electron scattering on disordered double barrier GaAs-Al$_x$Ga$_{1-x}$As heterostructures

摘要

We present a novel model to calculate vertical transport properties such asconductance and current in unintentionally disordered double barrierGaAs-Al$_x$Ga$_{1-x}$As heterostructures. The source of disorder comes frominterface roughness at the heterojunctions (lateral disorder) as well asspatial inhomogeneities of the Al mole fraction in the barriers (compositionaldisorder). Both lateral and compositional disorder break translational symmetryalong the lateral direction and therefore electrons can be scattered off thegrowth direction. The model correctly describe channel mixing due to theseelastic scattering events. In particular, for realistic degree of disorder, wehave found that the effects of compositional disorder on transport propertiesare negligible as compared to the effects due to lateral disorder.