STRAIN COMPENSATION IN LATTICE-MISMATCHED SHORT-PERIOD SUPERLATTICES

Citation
Js. Nelson et al., STRAIN COMPENSATION IN LATTICE-MISMATCHED SHORT-PERIOD SUPERLATTICES, Superlattices and microstructures, 23(5), 1998, pp. 1053-1062
Citations number
14
Categorie Soggetti
Physics, Condensed Matter
ISSN journal
07496036
Volume
23
Issue
5
Year of publication
1998
Pages
1053 - 1062
Database
ISI
SICI code
0749-6036(1998)23:5<1053:SCILSS>2.0.ZU;2-R
Abstract
The electronic properties of [001] (AlAs)(n)-(AlSb)(n) short-period st rained-layer-superlattices (SPSLS) lattice matched to InP, for n less than or equal to 4, have been calculated with a first-principles self- consistent pseudopotential method. The layer dependence of the interpl anar relaxations, direct and indirect band gaps, and spin-orbit and va lence band strain splittings are studied. Evolution of the superlattic e states from the bulk constituents is discussed in terms of wavefunct ion mixing and band repulsion due to zone-folding. The band structures of the SPSLSs are compared with a disordered alloy of AlAs0.5Sb0.5 re presented by the special quasirandom structure. We fmd that continuum models of the total valence band splitting (strain and spin-orbit) do not accurately represent the electronic structure of lattice mismatche d SPSLS, due to strong mixing of the heavy-and light-hole states acros s the interface. (C) 1998 Academic Press Limited.