Hydrogen-induced states near the GaAs band edges
Hydrogen-induced states near the GaAs band edges
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GaAs 能带边缘附近的氢诱导态
DOI：
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发表时间：
1999
期刊：
影响因子：
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通讯作者：
P. Giannozzi
中科院分区：
文献类型：
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作者：
A. A. Bonapasta;M. Capizzi;P. Giannozzi
在本研究中，我们研究了在GaAs中H物种的夹杂与近带边能级在带隙中的出现之间的联系。用第一性原理局域密度泛函方法计算了氢原子、离子和二聚体在GaAs晶格中不同位置的平衡几何构型和电子结构。为了区分H包裹体引起的晶格形变和H-主体键的形成对晶格形变的影响，我们还研究了与H原子不同平衡几何构型相同的原子排列，但去掉了H原子。在带隙中出现了离散的近边能级，这是由于H与GaAs晶格的相互作用以及H离子的电荷效应引起的。最后，从导带到价带近缘态的辐射跃迁解释了氢化III-V化合物光致发光光谱中观察到的发射带的主要特征。
In the present study the link between the inclusion of H species in GaAs and the appearance in the band gap of near-band-edge energy levels has been investigated. The equilibrium geometries and the electronic structures relative to different locations of H atoms, ions, and dimers in the GaAs lattice have been evaluated by first-principle local-density-functional methods. Atomic arrangements in GaAs identical to those found for different equilibrium geometries of the H species, but with the H species removed, have also been investigated in order to separate the effects of the lattice deformations due to the H inclusion from those produced by the formation of H-host-atom bonds. Discrete near-edge levels appear in the band gap, which are induced by the H interactions with the GaAs lattice as well as by charge effects in the case of H ions. Finally, radiative transitions from the conduction-band to the valence-band near-edge states are shown to account for the main features of the emission bands observed in the photoluminescence spectra of hydrogenated III-V compounds.