Large-Scale DFT Study of Ge/Si 3D Nanoislands and Core-Shell Nanowires
Large-Scale DFT Study of Ge/Si 3D Nanoislands and Core-Shell Nanowires
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Ge/Si 3D 纳米岛和核壳纳米线的大规模 DFT 研究
DOI：
10.1149/08607.0269ecst
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
T. Miyazaki
中科院分区：
文献类型：
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作者：
Ryo Tamura;Jianbo Lin;and Tsuyoshi Miyazaki;T. Miyazaki
密度泛函理论（DFT）计算在阐明半导体表面在原子尺度上的结构方面起着重要的作用。然而，复杂纳米结构的DFT研究通常是不可能的，因为传统的DFT方法不能处理包含数千个原子的大型系统。在本文中，我们使用我们的线性缩放DFT代码CONQUEST，对(i) Ge三维纳米结构在Si（001）衬底上的生长和（ii） Si/Ge或Ge/Si核壳纳米线的原子和电子结构进行了大规模的DFT研究。该代码采用大规模DFT技术，在大规模并行计算机上运行效率高。我们证明了CONQUEST可以计算实验中观察到的纳米结构真实模型的原子位置，并可以阐明这些纳米结构材料独特的电子特性。
Density functional theory (DFT) calculations have been playing important roles to clarify the structures of semiconductor surfaces at atomic scale. However, DFT studies of complex nanostructures are usually impossible because conventional DFT methods cannot treat large systems containing many thousands of atoms. In this paper, we survey our large scale DFT study on (i) the growth of Ge 3D nanostructure on Si (001) substrate and (ii) the atomic and electronic structures of Si/Ge or Ge/Si core-shell nanowires, using our linear-scaling DFT code CONQUEST. The code uses large-scale DFT techniques and has high efficiency on massively parallel computers. We demonstrate that CONQUEST can calculate the atomic positions of the realistic models of nanostructures observed in experiments and can clarify the unique electronic properties of these nano-structured materials.