应力下OsSi_2电子结构和光学特性研究  

The study on the electronic structure and optical properties of stressed OsSi_2

作　　者：李旭珍[1] 谢泉[1] 陈茜[1] 赵凤娟[1] 崔冬萌[1] 

机构地区：[1]贵州大学理学院,贵州大学新型光电子材料与技术研究所,贵阳550025

出　　处：《科学通报》2010年第9期746-751,共6页Chinese Science Bulletin

基　　金：国家自然科学基金(批准号:60766002);贵州省优秀科技教育人才省长专项基金(编号:Z053114);贵州省委组织部高层人才科研资助项目(编号:Z053123);科技部国际合作专项(编号:2008DFA52210);贵州省信息产业厅项目(编号:0831)资助

摘　　要：采用基于第一性原理的密度泛函理论(Density Functional Theory)赝势法,对各向同性形变下OsSi2的电子结构、态密度和光学性质进行了理论计算.计算结果表明,当晶格常数从96%,100%,104%依次进行各向同性形变时,OsSi2的带隙逐渐减小.当晶格参数被压缩到原来的96%时,OsSi2的间接带隙值Eg=0.928eV,当晶格参数被拉伸到原来的104%时,OsSi2的间接带隙值Eg=0.068eV.其光学特性曲线向低能方向漂移,晶格拉伸使得OsSi2的静态介电函数增大而压缩使其减小;晶格压缩可以使其吸收响应增强,进而提高光电转换效率.A detailed theoretical study of electronic structure, density of states and optical properties of OsSi2 under isotropic lattice deformation was performed by means of first-principles pseudopotential method. It was found that the isotropic lattice deformation results in the decrease in the energy gap from 96% lattice to 104% lattice. When the crystal lattice is 96% compressed, the indirect band gap is 0.928 eV; 104% stretched, the indirect band gap is 0.068 eV. Furthermore, the curve of optical properties tend to low-energy direction, When the crystal lattice is stretched, the static dielectric function increases; when compressed, the absorption enhances, and then improves the photoelectric conversion efficiency.

关 键 词：OsSi2 第一性原理 应力 电子结构 光学特性 

分 类 号：TN304.2[电子电信—物理电子学]