基于密度泛函理论的NiAs型MnTe第一原理计算  

First-principles calculations on MnTe of NiAs-type structure with density functional theory

作　　者：张思[1] 封文江[1] 朱影[1] 尹小荷[1] 郭帅帅[1] 何江海[1] 徐雅辉[1] 孟萍萍[1] 

机构地区：[1]沈阳师范大学物理科学与技术学院,沈阳110034

出　　处：《沈阳师范大学学报（自然科学版）》2014年第1期32-36,共5页Journal of Shenyang Normal University:Natural Science Edition

基　　金：辽宁省科学技术计划项目(2010220012);辽宁省教育厅高等学校优秀人才资助项目(LJQ2011117);沈阳师范大学实验中心重点项目(SYZX1003)

摘　　要：运用MaterialsStudio 6.0程序CASTEP软件包建立NiAs型MnTe单胞和1×1×10的超胞模型,采用GGA-PBE-TS近似,得出能带结构和态密度曲线。NiAs型MnTe为间接能隙窄带半导体,带隙为0.843eV;MnTe单胞的下价带在-12.5^-10.5eV,是一条二重简并带。在-6^-3.5eV和0.8~2.6eV主要由Mn原子的d态电子贡献,该Mn原子的d电子的有效质量较大,导致强的电子局域性;MnTe1×1×10超胞的帯隙为0.623eV,下价带位于-13^-11eV,对比单胞略微下移;在上价带和导带区域,MnTe超胞d态电子的能带和态密度都比MnTe单胞的变化平稳,整体形成较宽的赝能隙,说明Mn离子的共价性较强。The band structure and density of states（DOS） properties were calculated by CASTEP codes of Materials Studio 6.0, which were built as MnTe unit cell and 1×1×10 supercell, using generalized gradient approximation（GGA）. The calculated results show the MnTe is indirect and narrow-band semiconductor, the band gap is 0. 843 eV. The valence band at the under of the energy band diagram, in the region of -12. 5--10. 5 eV, is a double degenerate band. The atom of Mn is consisted of d-electron have a huge of active mass and intense electronic local at the section of - 6 -3.5 eV and 0. 8-2. 6 eV. The band gap of MnTe 1× 1× 10 supercell is 0. 623 eV, and the energy value of the downsite is --11--13 eV. By contrast with MnTe unit cell, there is a small decrease at the interval of --13--11 eV, the energy band and DOS are more stable at the d state. MnTe supercell take the shape of a wide pseudogap, explained Mn ion has a strong covalent.

关 键 词：NiAs型MnTe 能带结构 态密度 

分 类 号：O469[理学—凝聚态物理]