Heusler合金TiZrCoIn(100)表面结构、磁性及自旋极化率的第一性原理研究  

First-principles study on the surface structure,magnetism,and spin polarization of the quaternary Heusler alloy TiZrCoIn(100)surface

作　　者：陈英 王斌 陈少波 闫万珺 CHEN Ying;WANG Bin;CHEN Shao-Bo;YAN Wan-Jun(School of Mathematics and Physics,Anshun College,Anshun 561000,China;Anshun First Senior High School,Anshun 561000,China)

机构地区：[1]安顺学院数理学院,安顺561000 [2]安顺第一高级中学,安顺561000

出　　处：《原子与分子物理学报》2021年第6期151-156,共6页Journal of Atomic and Molecular Physics

基　　金：贵州省教育厅科研项目(黔教合KY字[2017]288);贵州省三方联合基金(黔科合LH字[2017]7041号);贵州省创新型项目(黔教合KY字[2016]048)。

摘　　要：本文利用第一性原理计算方法,对具有半金属性的四元Heusler合金TiZrCoIn两个不同终端表面效应进行了理论研究,主要针对表面效应对其结构、磁性、电子结构、自旋极化率及半金属性的影响来展开调研,以便寻求适合于隧道结的表面材料,为后续相关理论研究及实验提供一定参考.研究结果显示,两终端表面不同原子分别发生了不同程度的伸缩,同层原子发生错位,致使表面原子间距改变,进而改变它们之间的杂化作用,同时也影响着原子的磁矩.另外通过分析其态密度,发现TiCo-(100)和ZrIn-(100)两个终端表面由于受到表面效应的影响,其电子结构发生了很大的改变.块体TiZrCoIn原有的宽带隙和半金属性被表面态所破坏,但仍然保留着很高的自旋极化率,尤其是ZrIn-(100)终端表面,其费米面处呈现几乎100%的自旋极化率.Based on first-principles calculations,the surface effects on the structure,magnetism,electronic structure,spin polarization and half-metallicity of the different terminations of Heusler alloy TiZrCoIn(100)surface have been theoretically studied.The results show that different atoms on the surface have different degrees of expansion and dislocation.It causes dislocations of atoms in the same layer,resulting in the changes of the distance between atoms.This also changes the hybridization between them and affects the atomic magnetic moments.In addition,by analyzing the density of states,it is found that the electronic structures of TiCo-(100)and ZrIn-(100)terminal surfaces are greatly changed due to surface effects.The original wide band gap and the half-metallic properties of the TiZrCoIn bulk are destroyed by the surface states,but the two surfaces still retain a high spin polarization,especially,the ZrIn-(100)termination surface,its spin polarization at the Fermi level is almost 100%.

关 键 词：HEUSLER合金 表面 磁性 电子结构 自旋极化率 

分 类 号：O65[理学—分析化学]