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arXiv · 1003.3927

Many body effects in the excitation spectrum of a defect in SiC

Michel Bockstedte·Andrea Marini·Oleg Pankratov·Angel Rubio
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Abstract

We show that electron correlations control the photophysics of defects in SiC through both renormalization of the quasiparticle bandstructure and exciton effects. We consider the carbon vacancy, which is a well-identified defect with two possible excitation channels that involve conduction and valence band states. Corrections to the Kohn-Sham ionization levels are found to strongly depend on the occupation of the defect state. Excitonic effects introduce a red shift of 0.23 eV. The analysis unambigiously re-assigns excitation mechanism at the thresholds in photo-induced paramagnetic resonance measurements [J. Dashdorj \emph{et al.}, J. Appl. Phys. \textbf{104}, 113707 (2008)].

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Michel Bockstedte, Andrea Marini, Oleg Pankratov, Angel Rubio. 2010-03-20. Many body effects in the excitation spectrum of a defect in SiC. https://doi.org/10.1103/physrevlett.105.026401

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