ZnLaxS(n-x)(x=4，8)半导体材料光电性质的第一性原理计算  

First-principles calculation on theelectronic structures and optical properties of ZnLa_xS_(n-x)(x = 4,8)

作　　者：周虹君[1] 高一文[1] 

机构地区：[1]重庆文理学院物理系,重庆402160

出　　处：《原子与分子物理学报》2016年第1期156-160,共5页Journal of Atomic and Molecular Physics

摘　　要：本文采用第一性原理研究了Zn S,Zn La4Sn-4,Zn La8Sn-8三个体系的能带结构、分态密度、总态密度以及复介电函数.研究结果显示:Zn S体系的价带顶和导带底都在G点处,为直接带隙材料;Zn La4Sn-4,Zn La8Sn-8两体系的导带向价带移动,费米能级处有多条能级穿过,费米能级处附近的态密度则由S 3p,Zn3p和La 5d以及5p轨道组成;对比分析Zn S,Zn La4Sn-4,Zn La8Sn-8三个体系的复介电函数的虚部发现Zn La4Sn-4、Zn La8Sn-8体系在0-10e V区域内的介电峰都少于本征结构,而在10到20 e V的高能量区间内,Zn La4Sn-4、Zn La8Sn-8体系介电峰的相应幅度较Zn S增强.Employing first-principles calculations, we perform a systematic study of the band structure and densi- ty of states and complex dielectric function of ZnS, ZnLa4Sn-4, ZnLasSn-8. The conclusions include： Firstly, the band gap of the pure ZnS is a direct band gap material because the top of the valence band and the bottom of the conduction band are the same position for G point. Next in importance, the La impurity can change the distribution of electron density of states in the Fermi surface and some impurity levels appear in the Fermi surface. Near the Fermi level of the density of states is composed of Zn 3p and La 3p and S 5d 5p orbitals. Meanwhile, the an- alyzed imaginary part of the complex dielectric functions of ZnLa4Sn-4, ZnLasSn-8 can be found by the dielectric peak is less than the intrinsic structure in the region of 0 - 10 eV. In the high energy range of 10 to 20 eV, the dielectric peak of ZnLa4Sn-4, ZnLasSn-8 is stronger than ZnS.

关 键 词：第一性原理 ZNS 能带 态密度 

分 类 号：O469[理学—凝聚态物理]