Abstract
We investigate InxCd1-xO materials, where x = 0.0, 0.031, 0.063 and 0.125, to understand their high electrical conductivity and optical transparency windows, using the full-potential linearized augmented plane wave (FLAPW) method. In addition, we employ the screened exchange LDA (sX-LDA) method to evaluate accurate band structures including band gap that is underestimated by the LDA calculations. The results show a dramatic Burstein-Moss shift of the absorption edge by the In doping, reflecting the small effective mass of the Cd 5s conduction band. The calculated direct band gaps, 2.36 eV for x = 0.0 and 3.17 eV for x = 0.063, show excellent agreement with experiment. The effective mass of the conduction band of CdO is calculated to be 0.24 me (in the △ direction), in good agreement with an experimental value of 0.27 me, explaining its high electrical conductivity. The hybridization between the Cd 5s and the In 5s states yields complex many-body effects in the conduction bands: a hybridization gap in the conduction bands and a band-gap narrowing which cancels the further Burstein-Moss shift for higher In doping.
Original language | English (US) |
---|---|
Pages (from-to) | 101-105 |
Number of pages | 5 |
Journal | Thin Solid Films |
Volume | 411 |
Issue number | 1 |
DOIs | |
State | Published - May 22 2002 |
Event | TOEO-2 - Tokyo, Japan Duration: Nov 8 2001 → Nov 9 2001 |
Funding
Work at Northwestern University was supported by the NSF MRSEC Program through the Northwestern Materials Research Center (DMR-0076097) and the DOE through the National Renewable Energy Laboratory (Contract AAD-9-18668-05). We thank Dr O.N. Mryasov for helpful comments.
Keywords
- Band structure
- Optical properties
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Metals and Alloys
- Materials Chemistry