Origins of k · p errors for  GaAs/AlAs heterostructures
Energy Laboratory - Golden, CO 80401, USA
2 Department of Physics, Technion-Israel Institute of Technology - Haifa, 32000, Israel
Accepted: 3 January 1996
The method + envelope function combination used for semiconductor heterostructures is based on approximations dubious under some conditions. We directly compare 8-band with pseudopotential results for  GaAs/AlAs superlattices and quantum wells with all input parameters directly computed from bulk GaAs and AlAs pseudopotential bands. We find generally very good agreement for zone-center hole states within meV of the GaAs valence band maximum, but i) systematic errors deeper in the valence band and ii) qualitative errors for even the lowest conduction bands with appreciable contributions from off- zinc-blende states. We trace these errors to inadequate description of bulk GaAs and AlAs band dispersion away from the zone center.
PACS: 73.20.Dx – Electron states in low-dimensional structures (including quantum wells, superlattices, layer structures, and intercalation compounds) / 71.10.+x – General theories and computational techniques (including many-body perturbation theory, density-functional theory, atomic sphere approximation methods, Fourier decomposition methods, etc.)
© EDP Sciences, 1996