Zn_(1-x)Mg_xO电子结构及光学性质的第一性原理GGA+U方法研究  

First-principles GGA + U Investigation on The Electronic Structure and Optical Properties of Zn_(1-x)Mg_xO

作　　者：何旭[1,2] 武莉莉[1] 任胜强[1] 张静全[1] 都政[3] HE Xu;WU Li-li;REN Sheng-qiang;ZHANG Jing-quan;DU Zheng(College of Materials Science and Engineering,Sichuan University,Chengdu Textile College,National Supercomputing Center in Shenzhe)

机构地区：[1]四川大学材料科学与工程学院,四川成都610065 [2]成都纺织高等专科学校,四川成都611731 [3]国家超级计算深圳中心,广东深圳518055

出　　处：《发光学报》2018年第6期795-801,共7页Chinese Journal of Luminescence

基　　金：863国家高技术研究发展计划(2015AA050610)资助项目~~

摘　　要：Mg掺杂ZnO形成的固溶体Zn_(1-x)Mg_xO(ZMO)(0≤x≤0.25)是一种带隙较宽、电子学性质可调控的半导体材料,在薄膜太阳电池及光电设备的透明电极等方面具有重要的应用价值。基于密度泛函理论下的第一性原理超软赝势方法,采用GGA+U计算了ZMO的电子结构和光学性质。计算结果表明,随着x值的增加,ZMO的禁带宽度由x=0时的3.32eV增加到x=0.25时的3.78eV;光吸收边及反射谱和能量损失谱均发生明显蓝移,峰值存在于紫外光区。计算结果与实验结论相符合。Mg substitution in ZnO can form ternary alloys Zn（1-x）MgxO（ZMO）（0≤x≤0.25）which has wide band gap and tunable electronic properties.So ZMO has a large application in transparency electrode of thin-film solar cells and optoelectronic device.The electronic structure and optical properties of ZMO ternary alloys were calculated using first-principles calculations based on the density functional theory combined with GGA＋U approach.The calculation results show that the doping of magnesium leads to an apparent change of the electronic structure of ZMO.With Mg concentration increasing,the band gap of ZMO widens from 3.32 e V（x=0）to 3.78 e V（x=0.25）.In addition,the absorption edge exhibits a blue shift with Mg concentration increasing.At the same time,the reflectivity and loss-function show mainly in the ultra-violet region,which is similar to those of optical absorption.The calculation results are in good agreement with the experiment.

关 键 词：ZMO 第一性原理 电子结构 光学性质 

分 类 号：O471.5[理学—半导体物理] O472.3[理学—物理]