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Zn-related deep centers in wurtzite GaN

Fabio Bernardini·Vincenzo Fiorentini·R. M. Nieminen
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Abstract

Zn in GaN forms an efficient radiative center and acts as a deep acceptor which can make the crystal insulating. Four different Zn-related centers have been by now identified, leading to light emission in the range between 1.8 eV and 2.9 eV. We present a first-principles investigation total energy and electronic structure calculations for Ga-substitutional and hetero-antisite N-substitutional Zn in wurtzite GaN, using ultrasoft pseudopotentials and a conjugate-gradient total energy minimization method. Our results permit the identification of the blue-light emission center as the substitutional acceptor, while contrary to a common belief the Zn_N heteroantisite has a very high formation energy and donor behavior, which seems to exclude it as the origin of the other centers.

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Fabio Bernardini, Vincenzo Fiorentini, R. M. Nieminen. 1996-10-07. Zn-related deep centers in wurtzite GaN. https://arxiv.org/abs/cond-mat/9610044

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