光学学报, 2017, 37 (5): 0516002, 网络出版: 2017-05-05
AlN1-xPx合金电子结构及光学性质的第一性原理研究 下载: 541次
First-Principles Study of Electronic Structure and Optical Property of AlN1-xPx Alloys
材料 第一性原理 电子结构 光学性质 materials AlN1-xPx AlN1-xPx first-principles electronic structure optical property
摘要
基于密度泛函理论第一性原理的平面波超软赝势, 采用广义梯度近似及Heyd-Scuseria-Ernzerhof 03 (HSE03)方法对能带及态密度进行修正, 研究了AlN1-xPx(x=0, 0.25, 0.50, 0.75, 1)合金的晶体结构、电子结构和光学性质。结果表明, 随P含量的增加, AlN1-xPx晶格常数呈线性递增趋势, AlN1-xPx(x=0, 0.25, 0.75, 1)属于立方晶系, 而AlN0.50P0.50属于四方晶系。AlN1-xPx带隙随P含量的增加呈先减后增趋势, AlN和AlP是间接带隙半导体, 而AlN1-xPx(x=0.25, 0.50, 0.75)属于直接带隙半导体。P的存在破坏了AlN原本的本征值和简并态, 改变了电子能带结构。随P含量的增加, AlN1-xPx的光学性质曲线向低能区移动, 介电函数虚部的次强峰逐渐消失。AlN1-xPx合金对紫外光具有较强吸收, P的存在拓宽了可见光吸收范围。
Abstract
Based on the plane-wave ultra-soft pseudo-potential in the first-principles of density functional theory and by using the generalized gradient approximation and the Heyd-Scuseria-Ernzerhof 03 (HSE03) method to correct the energy bands and density of states, the crystal structure, the electronic structure and the optical property of AlN1-xPx (x=0, 0.25, 0.50, 0.75, 1) alloys are studied. The results show that the lattice constant of AlN1-xPx alloys increases linearly as the P component increases. AlN1-xPx (x=0, 0.25, 0.75, 1) alloys are of the cubic system, while AlN0.50P0.50 alloy belongs to the tetragonal system. The band gap of AlN1-xPx alloys firstly decreases and then increases as the P component increases. AlN and AlP alloys are the indirect band gap semiconductors, while AlN1-xPx (x=0.25, 0.50, 0.75) alloys belong to the direct band gap semiconductors. The presence of P destroys the original eigenvalues and the degenerate states of AlN, and changes the electronic band structures. As the P component increases, the optical characteristic curves of AlN1-xPx move towards the low energy region, and the subsidiary strong peaks of the imaginary parts of dielectric functions gradually fade away. AlN1-xPx alloys can absorb the ultraviolet light strongly and the presence of P can broaden the absorption region of visible light.
侯嘉慧, 贺达芳, 陈晶晶, 李春梅, 程南璞. AlN1-xPx合金电子结构及光学性质的第一性原理研究[J]. 光学学报, 2017, 37(5): 0516002. Hou Jiahui, He Dafang, Chen Jingjing, Li Chunmei, Cheng Nanpu. First-Principles Study of Electronic Structure and Optical Property of AlN1-xPx Alloys[J]. Acta Optica Sinica, 2017, 37(5): 0516002.