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 MSCE  Vol.4 No.11 , November 2016
The Effect on the Electric Structure and Optical Properties of Ca2Ge Bulk with Sr-Doping
Abstract: The electronic structure and the optical properties of Ca2Ge have been calculated by the first-principles pseudo potential method. The results of the electric structure show that Ca2Ge bulk is a direct semiconductor with the band gap of 0.306 eV, the conduction band is mainly composed of Ca 3d, the valence bands is mainly composed of Ge 3p. With Sr-doping, Ca2Ge bulk is a direct semiconductor with the band gap of 0.350 eV, the conduction bands are mainly composed of Ca 3d and Sr 3d, the valence bands are mainly composed of Ge 3p and Sr 3d. The results of the optical properties show that the dielectric constant of Ca2Ge bulk is reduced from 21.52 to 13.94, the reflectivity is decreased, and the absorption is increased with Sr-doping. The optical properties are improved with Sr-doping, the results offer theoretical guide for the optical properties control of Ca2Ge.
Cite this paper: Wei, Y. , Yang, Y. , Cen, W. , Li, R. and Lv, L. (2016) The Effect on the Electric Structure and Optical Properties of Ca2Ge Bulk with Sr-Doping. Journal of Materials Science and Chemical Engineering, 4, 20-26. doi: 10.4236/msce.2016.411003.
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