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arXiv · 0904.2140

Unraveling the Jahn-Teller effect in Mn doped GaN using the Heyd-Scuseria-Ernzerhof hybrid functional

A. Stroppa·G. Kresse
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Abstract

We present an ab-initio study of the Mn substitution for Ga in GaN using the Heyd-Scuseria-Ernzerhof hybrid functional (HSE). Contrary to semi-local functionals, the majority Mn t$_{2}$ manifold splits into an occupied doublet and an unoccupied singlet well above the Fermi-level resulting in an insulating groundstate, which is further stabilized by a sizeable Jahn-Teller distortion. The predictions are confirmed using $GW$ calculations and are in agreement with experiment. A transition from a localized to a delocalized Mn hole state is predicted from GaN to GaAs.

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A. Stroppa, G. Kresse. 2009-04-14. Unraveling the Jahn-Teller effect in Mn doped GaN using the Heyd-Scuseria-Ernzerhof hybrid functional. https://doi.org/10.1103/physrevb.79.201201

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