Ab-initio electronic structure calculation of the InAs multiple quantum wells in bulk GaAs

We present a theoretical investigation of the electronic structure of an InAs monomolecular plane inserted in bulk GaAs. Our calculations are based on the ab-initio self-consistent pseudopotential method. Both electrons and holes are found to be strongly localized in the vicinity of the inserted InAs monolayer, which therefore acts as a quantum well for all charge carriers. Moreover, using a finite-square-well model, we show that the energy gap increases with the increasing GaAs barrier thickness and also show the formation of a localized electron/hole state in the gap in the limit of a single InAs quantum well. This latter result successfully explains the intense and narrow low temperature photoluminescence spectra, experimentally observed in the InAs/GaAs single-monolayer quantum well systems.