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arXiv · 1301.4126

The role of screening in the density functional applied on transition metal defects in semiconductors

V. Ivády·I. A. Abrikosov·E. Janzén·A. Gali
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Abstract

We study selected transition metal related point defects in silicon and silicon carbide semiconductors by a range separated hybrid density functional (HSE06). We find that HSE06 does not fulfill the generalized Koopmans' Theorem for every defect which is due to the self-interaction error in the functional in such cases. Restoring the so-called generalized Koopmans' Condition with a simple correction in the functional can eliminate this error, and brings the calculated charge transition levels remarkably close to the experimental data as well as to the calculated quasi-particle levels from many-body perturbation theory.

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V. Ivády, I. A. Abrikosov, E. Janzén, A. Gali. 2013-01-17. The role of screening in the density functional applied on transition metal defects in semiconductors. https://doi.org/10.1103/physrevb.87.205201

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