关于Zn1-xBexO电子结构和光学性质的研究

采用基于密度泛函理论和平面波赝势技术的CASTEP程序对Zn_1-xBe_xO合金电子结构和光学性质进行了计算.当0≤x≤1，其带隙从0.963 eV变化到7.293 eV.分析了晶格畸变和能带间排斥效应对带隙的影响.当Be含量x=0.125，0.25，0.375，0.5，0.625，0.75时，a/b轴压应变控制着带隙变化；当x=0.875，1时，c轴压应变控制着带隙变化.能带间的p-d排斥影响价带顶变动，Γ_1v与Γ_1c之间排斥影响导带底变动.这些能带间的排斥效应被用来分析Zn_1-xBe_xO带隙变动.另外，也分析了Zn_1-xBe_xO介电函数虚部ε₂. 关键词： 带结构 光学性质 应变 排斥

A study on electronic structure and optical properties of Zn1-x BexO

In the paper，electronic structure and optical properties of Zn_1-xBe_xO are calculated by CASTEP program based on density functional theory and plane-wave pseudopotential method. The band gap increases in the range from 0.963 eV to 7.293 eV when Be content changes from 0 to 1. The lattice strain and band repulsion affecting band gap is investigated. The variation of the band gap is dominated by a/b-axis strain for x=0.125，0.25，0.375，0.5，0.625 and 0.75. The variation of the band gap is dominated by c-axis strain for x=0.875 and 1. In the paper，p-d and Γ_1v-Γ_1c repulsion are used to investigate the top of valence band and the bottom of conduction band，respectively. In addition，we also investigate the imaginary part of the dielectric function，ε₂ of Zn_1-xBe_xO.