Deep Level Induced Formation of Wide Minibands in a Light-Binding Superlattice: Transition from Localized to Extended States
30 November 1987
In a tight binding superlattice, due to the weak coupling between wells, the minibands are very narrow ( 1 meV for many representative III-V multiquantum well structures such as GaAs/AlGaAs). The ever present intralayer thickness fluctuations (~ 1 monolayer), compositional fluctuations, and phonon scattering will produce a broadening of the superlattice states which is larger than the miniband width, leading to localization of the states.