Electronic and optical properties of beryllium chalcogenide/silicon heterostructures
Abstract
We have calculated electronic and optical properties of Si/BeSe0.41Te0.59 heterostructures by a semiempirical sp3s* tight-binding method. Tight-binding parameters and band bowing of BeSe0.41Te0.59 are considered through a recent model for highly mismatched semiconductor alloys. The band bowing and the measurements of conduction band offset lead to a type II heterostucture for Si/BeSe0.41Te0.59 with the conduction band minimum in the Si layer and the valence band maximum in the BeSe0.41Te0.59 layer. The electronic structure and optical properties of various (Si2)n/(BeSe0.41Te0.59)m [001] superlattices have been considered. Two bands of interface states were found within the band gap of bulk Si. Our calculations indicate that the optical edges are below the fundamental band gap of bulk Si and the transitions are optically allowed.
- Publication:
-
Physical Review B
- Pub Date:
- June 2006
- DOI:
- 10.1103/PhysRevB.73.235307
- arXiv:
- arXiv:cond-mat/0608514
- Bibcode:
- 2006PhRvB..73w5307S
- Keywords:
-
- 73.21.Cd;
- 73.21.Fg;
- 78.67.De;
- Superlattices;
- Quantum wells;
- Condensed Matter - Materials Science;
- Condensed Matter - Mesoscale and Nanoscale Physics
- E-Print:
- 16 pager, 7 figures