六方Fe_(2)Ge合金块体及其(001)表面电子结构和磁性的第一性原理  

First-Principle Study on Electronic Structure and Magnetic Properties of Bulk and Its (001) Surfaces of Hexagonal Fe_(2)Ge Alloy

作　　者：陈聪 岑伟富 熊启杭 吕林 姚冰 杨吟野 CHEN Cong;CEN Weifu;XIONG Qihang;LYU Lin;YAO Bing;YANG Yinye(School of Physics Mechatronic Engineering,GuiZhou Minzu University,Guiyang 550025,China;School of Materials Science and Engineering,Guizhou Minzu University,Guiyang 550025,China;Engineering Training Center,Guizhou Minzu University,Guiyang 550025,China)

机构地区：[1]贵州民族大学物理与机电工程学院,贵阳550025 [2]贵州民族大学材料科学与工程学院,贵阳550025 [3]贵州民族大学工程实训中心,贵阳550025

出　　处：《人工晶体学报》2022年第11期1895-1902,共8页Journal of Synthetic Crystals

基　　金：Science and Technology Foundation of Guizhou Province (1Y[2020]200,1Y[2020]205)。

摘　　要：采用基于密度泛函理论第一性原理的赝势平面波方法,计算了块体Fe_(2)Ge及其(001)表面的电子结构和磁性。考虑了两种类型的终端(001)表面:Ge(Ⅰ)-(001)表面和Ge(Ⅱ)-(001)表面。电子结构方面,不同类型的Fe_(2)Ge(001)表面都表现出金属特性,这与块体的金属性保持一致。通过计算它们的自旋极化率,得出Ge(Ⅰ)-(001)表面的自旋极化程度最高。磁性方面,在块体和Ge(Ⅱ)-(001)表面的Ge原子是铁磁自旋有序的,而在Ge(Ⅰ)-(001)表面第一层的Ge原子是亚铁磁自旋有序的。此外,Ge(Ⅱ)-(001)表面Ge原子的自旋磁矩优于块体中和Ge(Ⅰ)-(001)表面Ge原子的自旋磁矩。这些结果与Fe的d态和Ge的p态电子的杂化有关,本文中通过分析它们的态密度进行了讨论。The electronic structures and magnetic properties of the bulk Fe_(2)Ge and its(001)surfaces were calculated by the pseudo-potential plane wave method based on the first-principle of density functional theory.Here,two types of the terminated(001)surfaces were considered:Ge(Ⅰ)-(001)surface and Ge(Ⅱ)-(001)surface.For the electronic structures,the different types of the Fe_(2)Ge(001)surfaces all show metallic characteristics,which are in agreement with the bulk counterpart.For the magnetism,the Ge atoms are ferromagnetic spin ordering in the bulk and Ge(Ⅱ)-(001)surface,while the Ge atoms are ferrimagnetic spin ordering in the first layer of the Ge(Ⅰ)-(001)surface.Moreover,the spin magnetic moment of the Ge atoms in the Ge(Ⅱ)-(001)surface are better than those of the bulk and Ge(Ⅰ)-(001)surface.These results are related to the hybridization between the Fe d and Ge p states,which were discussed by analyzing their density of states.

关 键 词：Fe2Ge(001)表面 电子结构 磁性 第一性原理 密度泛函理论 自旋极化率 

分 类 号：O469[理学—凝聚态物理] O485[理学—电子物理学] O737[理学—物理] O738