AlN_(1-x)P_x合金电子结构及光学性质的第一性原理研究  

First-Principles Study of Electronic Structure and Optical Property of AlN_(1-x)P_x Alloys

作　　者：侯嘉慧 贺达芳 陈晶晶[1] 李春梅[1] 程南璞[1] 

机构地区：[1]西南大学材料与能源学部,重庆400715

出　　处：《光学学报》2017年第5期234-242,共9页Acta Optica Sinica

基　　金：国家自然科学基金(51171156;51601153);重庆市基础科学与前沿技术研究(CSTC2014JCYJYS0001)

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AlN_(1-x)P_x(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,AlN_(1-x)P_x晶格常数呈线性递增趋势,AlN_(1-x)P_x(x=0,0.25,0.75,1)属于立方晶系,而AlN0.50P0.50属于四方晶系。AlN_(1-x)P_x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AlN_(1-x)P_x(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,AlN_(1-x)P_x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。AlN_(1-x)P_x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。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-x Px （ 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.

关 键 词：材料 AlN1-xPx 第一性原理 电子结构 光学性质 

分 类 号：O474[理学—半导体物理] O471.5[理学—物理]