Band Structure of Semiconductor Superlattices with Ultrathin Layers (GaAs)n/(AlAs)nwithn=1, 2, 3, 4
- 15 December 1985
- journal article
- research article
- Published by Physical Society of Japan in Journal of the Physics Society Japan
- Vol. 54 (12) , 4726-4734
- https://doi.org/10.1143/jpsj.54.4726
Abstract
The band structures of ultrathin layered superlattices (GaAs) n /(AlAs) n with n =1, 2, 3 and 4 are calculated by the self-consistent pseudopotential method. In this calculalion a value of α in the Xα approximation for the exchange-correlation potential is adjusted so as to reproduce both band gaps of GaAs and AlAs. This reflects an effect of the self-energy correction. The resulting band structures and charge densities show that upper valence band states of (GaAs) n /(AlAs) n with n =1 to 4 are approximately obtained by folding the valence bands of GaAs and AlAs, while that lower conduction band states correspond to strong hybridization of folded bands of GaAs and AlAs. It is shown that the band gap of (GaAs) 1 /(AlAs) 1 is indirect, while those for n =2 to 4 are direct and decrease with increasing n. This trend is consistent with recent experimental results.Keywords
This publication has 6 references indexed in Scilit:
- Self-consistent calculation of properties of GaAs-AlAs superlattices with homopolar interfacesPhysical Review B, 1982
- Self-interaction correction to density-functional approximations for many-electron systemsPhysical Review B, 1981
- Similarity of (Ga, Al, As) alloys and ultrathin heterostructures: Electronic properties from the empirical pseudopotential methodPhysical Review B, 1980
- Energy bands in neon and argonPhysics Letters A, 1980
- Self-consistent calculations of interface states and electronic structure of the (110) interfaces of Ge-GaAs and AlAs-GaAsPhysical Review B, 1978
- Epitaxial structures with alternate-atomic-layer composition modulationApplied Physics Letters, 1976