AB INITIO STUDY OF NITROGEN ANTISITES IN GaN AND AlN
نویسندگان
چکیده
We present results of an ab initio study of the nitrogen antisite defect in GaN and AlN. We show that the neutral antisite in zinc-blende structure exhibits metastable behaviour similar to the arsenic antisite in GaAs, but in the wurtzite structure the phenomenon does not exist. A new discovery is that the negative charge states of the nitrogen antisite are stabilized by the large band gap. In the negative charge states a large spontaneous Jahn-Teller displacement of the nitrogen antisite is observed in the 111] direction, both in the zinc-blende and in the wurtzite phase. We discuss the possible connection between the nitrogen antisite and the yellow luminescence commonly observed in GaN.
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