Tu Haoran, Zhang Jing, Guo Zexuan, Xu Chunyan
Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), Department of Physics, Jilin University Changchun 130012 China.
Institute for Interdisciplinary Quantum Information Technology, Jilin Engineering Normal University Changchun 130052 China
RSC Adv. 2019 Dec 19;9(72):42245-42251. doi: 10.1039/c9ra08634j. eCollection 2019 Dec 18.
Silicene-based materials have attracted great attention due to their easier incorporation into silicon-based devices and components. In addition to the reported hydrogenated 2D tetragonal silicene (γ-SiH), we propose two stable atomic configurations of hydrogenated 2D tetragonal silicene (α-SiH and β-SiH) based on first-principles calculation. The calculated results indicate hydrogenation can effectively open the band gap of 2D tetragonal silicene, α-SiH is a semiconductor with a direct band gap of 2.436 eV whereas β-SiH is indirect band gap of 2.286 eV. We also find that the electronic band structure of α-SiH, β-SiH and γ-SiH can be modulated biaxial strain. By applying biaxial strain in the range of -10% to 12%, the band gap of α-SiH, β-SiH and γ-SiH can be tuned in a range of 1.732-2.585 eV. Furthermore, direct-indirect or indirect-direct transition can be induced under biaxial strain, showing a high degree of flexibility in electronic band structure. The research not only broadens the diversity of hydrogenated 2D tetragonal silicenes, but also provides more possibilities of their applications in spintronic devices.
基于硅烯的材料因其更容易集成到硅基器件和组件中而备受关注。除了已报道的氢化二维四方硅烯（γ-SiH）外，我们基于第一性原理计算提出了两种氢化二维四方硅烯的稳定原子构型（α-SiH和β-SiH）。计算结果表明，氢化可以有效地打开二维四方硅烯的带隙，α-SiH是一种直接带隙为2.436 eV的半导体，而β-SiH是间接带隙为2.286 eV的半导体。我们还发现，α-SiH、β-SiH和γ-SiH的电子能带结构可以通过双轴应变进行调制。在-10%至12%的范围内施加双轴应变时，α-SiH、β-SiH和γ-SiH的带隙可以在1.732-2.585 eV的范围内进行调节。此外，在双轴应变下可以诱导直接-间接或间接-直接跃迁，这表明电子能带结构具有高度的灵活性。该研究不仅拓宽了氢化二维四方硅烯的多样性，还为其在自旋电子器件中的应用提供了更多可能性。
