中国物理B ›› 2014, Vol. 23 ›› Issue (5): 56301-056301.doi: 10.1088/1674-1056/23/5/056301

• CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES • 上一篇    下一篇

Effect of Gd doping on the magnetism and work function of Fe1-xGdx/Fe (001)

汤可嵚, 钟克华, 程燕铭, 黄志高   

  1. College of Physics and Energy, Fujian Normal University, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, Fuzhou 350108, China
  • 收稿日期:2013-08-03 修回日期:2013-10-23 出版日期:2014-05-15 发布日期:2014-05-15
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 11004039) and the National Basic Research Program of China (Grant No. 2011CBA00200).

Effect of Gd doping on the magnetism and work function of Fe1-xGdx/Fe (001)

Tang Ke-Qin (汤可嵚), Zhong Ke-Hua (钟克华), Cheng Yan-Ming (程燕铭), Huang Zhi-Gao (黄志高)   

  1. College of Physics and Energy, Fujian Normal University, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, Fuzhou 350108, China
  • Received:2013-08-03 Revised:2013-10-23 Online:2014-05-15 Published:2014-05-15
  • Contact: Huang Zhi-Gao E-mail:zghuang@fjnu.edu.cn
  • About author:63.20.dk; 75.70.-i; 65.40.gh; 75.50.Bb
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 11004039) and the National Basic Research Program of China (Grant No. 2011CBA00200).

摘要: The magnetism and work function Φ of Fe1-xGdx/Fe (001) films have been investigated using first-principles methods based on the density functional theory. The calculated results reveal that Gd doping on the Fe (001) surface would greatly affect the geometrical structure of the system. The restruction of the surface atoms leads to the transition of magnetic coupling between Gd and Fe atoms from ferromagnetic (FM) for 0.5 ≤ x ≤ 0.75 to antiferromagnetic (AFM) for x=1.0. For Fe1-xGdx/Fe (001) (x=0.25, 0.5, 0.75, 1.0), the charge transfer from Gd to Fe leads to a positive dipole formed on the surface, which is responsible for the decrease of the work function. Moreover, it is found that the magnetic moments of Fe and Gd on the surface layer can be strongly influenced by Gd doping. The changes of the work function and magnetism for Fe1-xGdx/Fe (001) can be explained by the electron transfer, the magnetic coupling interaction between Gd and Fe atoms, and the complex surface restruction. Our work strongly suggests that the doping of the metal with a low work function is a promising way for modulating the work function of the magnetic metal gate.

关键词: first-principles method, doping, magnetism, work function

Abstract: The magnetism and work function Φ of Fe1-xGdx/Fe (001) films have been investigated using first-principles methods based on the density functional theory. The calculated results reveal that Gd doping on the Fe (001) surface would greatly affect the geometrical structure of the system. The restruction of the surface atoms leads to the transition of magnetic coupling between Gd and Fe atoms from ferromagnetic (FM) for 0.5 ≤ x ≤ 0.75 to antiferromagnetic (AFM) for x=1.0. For Fe1-xGdx/Fe (001) (x=0.25, 0.5, 0.75, 1.0), the charge transfer from Gd to Fe leads to a positive dipole formed on the surface, which is responsible for the decrease of the work function. Moreover, it is found that the magnetic moments of Fe and Gd on the surface layer can be strongly influenced by Gd doping. The changes of the work function and magnetism for Fe1-xGdx/Fe (001) can be explained by the electron transfer, the magnetic coupling interaction between Gd and Fe atoms, and the complex surface restruction. Our work strongly suggests that the doping of the metal with a low work function is a promising way for modulating the work function of the magnetic metal gate.

Key words: first-principles method, doping, magnetism, work function

中图分类号:  (First-principles theory)

  • 63.20.dk
75.70.-i (Magnetic properties of thin films, surfaces, and interfaces) 65.40.gh (Work functions) 75.50.Bb (Fe and its alloys)