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arXiv · 0705.2550

Electronic structure and optical properties of ZnX (X=O, S, Se, Te)

S. Zh. Karazhanov·P. Ravindran·A. Kjekshus·H. Fjellvag·B. G. Svensson
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Abstract

Electronic band structure and optical properties of zinc monochalcogenides with zinc-blende- and wurtzite-type structures were studied using the ab initio density functional method within the LDA, GGA, and LDA+U approaches. Calculations of the optical spectra have been performed for the energy range 0-20 eV, with and without including spin-orbit coupling. Reflectivity, absorption and extinction coefficients, and refractive index have been computed from the imaginary part of the dielectric function using the Kramers--Kronig transformations. A rigid shift of the calculated optical spectra is found to provide a good first approximation to reproduce experimental observations for almost all the zinc monochalcogenide phases considered. By inspection of the calculated and experimentally determined band-gap values for the zinc monochalcogenide series, the band gap of ZnO with zinc-blende structure has been estimated.

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S. Zh. Karazhanov, P. Ravindran, A. Kjekshus, H. Fjellvag, B. G. Svensson. 2007-05-17. Electronic structure and optical properties of ZnX (X=O, S, Se, Te). https://doi.org/10.1103/physrevb.75.155104

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