MnGa合金体的电子结构与磁性质的研究

人工晶体学报 ›› 2022, Vol. 51 ›› Issue (1): 65-71.

MnGa合金体的电子结构与磁性质的研究

张飞鹏¹, 路清梅², 李虹霏², 房慧³, 刘卫强², 张东涛², 岳明²

1.河南城建学院数理学院,建筑光伏一体化技术河南省工程实验室, 平顶山 467036;
2.北京工业大学材料与制造学部,北京 100124;
3.广西民族师范学院物理与电子工程学院,崇左 532200

收稿日期:2021-10-11 出版日期:2022-01-15 发布日期:2022-02-09
通讯作者: 路清梅,博士,教授。E-mail:qmlu@bjut.edu.cn
作者简介:张飞鹏(1980—),男,河南省人,博士,副教授。E-mail:zhfp163@163.com
基金资助:
国家自然科学基金(51771003);北京市自然科学基金(2202006);广西高等学校千名骨干教师培育计划;广西民族师范学院重点学科建设项目;广西民族师范学院科研创新团队项目;广西民族师范学院教授科研启动项目(2020JS001)

Electronic Structure and Magnetic Properties of MnGa Alloy

ZHANG Feipeng¹, LU Qingmei², LI Hongfei², FANG Hui³, LIU Weiqiang², ZHANG Dongtao², YUE Ming²

1. Henan Provincial Key Engineering Lab of Building-photovoltaics, Department of Mathematics and Physics, Henan University of Urban Construction, Pingdingshan 467036, China;
2. Department of Materials and Manufacturing, Beijing University of Technology, Beijing 100124, China;
3. Academy of Physics and Electronic Engineering, Guangxi Normal University for Nationalities, Chongzuo 532200, China

Received:2021-10-11 Online:2022-01-15 Published:2022-02-09

摘要/Abstract

摘要： 基于密度泛函理论方法系统研究了四方结构MnGa合金体的结构、形成、电子结构和磁性质。结果表明,四方MnGa合金晶胞的生成焓为-4.85 eV,高于一些不含d电子的体系。其呈现导体的能带结构,其中d电子主要形成深能级价带,定域性最强。四方MnGa合金存在着明显的自旋极化,靠近费米能级两侧的s电子和靠近费米能级下方的p电子具有较弱的自旋极化。形成浅能级价带和导带的d电子产生高强度的自旋极化,对磁性质贡献较大。Mn的s电子和Mn的p电子自旋极化作用较弱,Mn的d电子形成浅能级价带和导带,自旋极化作用最强。形成深能级价带的Ga的d电子自旋极化作用较弱,不同位置的Ga原子的自旋极化不同。四方MnGa合金体具有净有效磁矩,呈弱的亚铁磁性。

关键词: 磁性材料, MnGa合金, 电子结构, 磁性质, 密度泛函理论

Abstract: Geometry, formation, electronic structure as well as magnetic properties of the tetragonal MnGa alloy were systematically studied by density functional theory method. The results show that the tetragonal MnGa has formation enthalpy of -4.85 eV, which is slightly higher than other compounds without d state electrons. It has conductor like band structure with the deep valance bands formed by d state electrons, they show strong localization effect. The tetragonal MnGa alloy shows obvious spin polarization. The s state electrons near Fermi energy and the p state electrons under Fermi energy have weak spin polarization, the d state electrons which form conductor band and bands below Fermi energy have strong spin polarization, they contribute to the total electronic as well as magnetic properties. The s and p state electrons of Mn have weak spin polarization, its d electrons which form conductor band and bands below Fermi energy have strongest spin polarization. The d electrons of Ga which form bands below Fermi energy have weak spin polarization. The two kinds of Ga have different spin polarization states. The tetragonal MnGa alloy has net magnetic moment, it shows weak ferrimagnetism.

Key words: magnetic material, MnGa alloy, electronic structure, magnetic property, density functional theory method

中图分类号:

TG132.2
O469

张飞鹏, 路清梅, 李虹霏, 房慧, 刘卫强, 张东涛, 岳明. MnGa合金体的电子结构与磁性质的研究[J]. 人工晶体学报, 2022, 51(1): 65-71.

ZHANG Feipeng, LU Qingmei, LI Hongfei, FANG Hui, LIU Weiqiang, ZHANG Dongtao, YUE Ming. Electronic Structure and Magnetic Properties of MnGa Alloy[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2022, 51(1): 65-71.

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