Dual nature of acceptors in GaN and ZnO: The curious case of the shallow MgGa deep state
Dual nature of acceptors in GaN and ZnO: The curious case of the shallow MgGa deep state
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DOI：
10.1063/1.3383236
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发表时间：
2010-04-05
影响因子：
4
通讯作者：
Zunger, Alex
中科院分区：
文献类型：
--
作者：
Lany, Stephan;Zunger, Alex
采用Koopmans修正的密度泛函方法，我们发现，金属位受主Mg，Be，Zn在GaN和Li在ZnO绑定空穴在深层次上，主要是本地化在单个阴离子配体原子。除了这个深基态（DGS），我们观察到一个有效的masslike离域状态，可以存在一个短暂的浅瞬态（STS）。GaN中的Mg掺杂剂代表了局部深能级的电离能仅略微超过浅有效质量受体的电离能的独特情况，这解释了为什么Mg作为受体掺杂剂如此出色地工作。
Employing a Koopmans corrected density functional method, we find that the metal-site acceptors Mg, Be, and Zn in GaN and Li in ZnO bind holes in deep levels that are largely localized at single anion ligand atoms. In addition to this deep ground state (DGS), we observe an effective-masslike delocalized state that can exist as a short lived shallow transient state (STS). The Mg dopant in GaN represents the unique case where the ionization energy of the localized deep level exceeds only slightly that of the shallow effective-mass acceptor, which explains why Mg works so exceptionally well as an acceptor dopant.