Band structures of GaAs, InAs, and Ge: A 24-k.p model

We present a generalized theoretical description of the 24x24 k.p approach for determining the band structure of the direct-band-gap semiconductors (GaAs, InAs) as well as the indirect-band-gap semiconductor (Ge), including far-level contribution (essentially the d levels). We extend the sp(3)s(*) basis functions by the inclusion of s(V)(*) orbitals. We find that the sp(3)d(s(*))(2) k.p model is fairly sufficient to describe the electronic structure of these systems over a wide energy range, obviating the use of any d orbitals. Finally, the comparison with available experimental and theoretical results shows that the present model reproduces known results for bulk GaAs, InAs, and Ge, that is, their band structure, including s and p valence bands and the lowest two conduction bands. (C) 2003 American Institute of Physics.