Abstract <p>The temperature dependences of the electrical resistivity of five (Cu<sub>1–<i>x</i></sub>Co<sub><i>x</i></sub>)<sub>2</sub>MnAl (<i>x</i> = 0, 0.25, 0.5, 0.75, 1) Heusler alloys have been experimentally investigated at temperatures from 78 to 300 K, and calculations of the electronic structure within the framework of the density functional theory, performed for them. It is shown that upon transition from a Cu<sub>2</sub>MnAl ferromagnet to a Co<sub>2</sub>MnAl topological semimetal, the electronic structure is rearranged, thus leading to significant changes in the electrical resistivity: its value changes by more than an order of magnitude, and the curvature of its temperature dependences changes from positive to negative. The latter correlates with an increase in the partial density of the 3<i>d</i> states at the Fermi level, which enhances the <i>s</i>–<i>d</i> interband scattering and leads to a contribution to the resistivity ρ, which is responsible for the negative curvature of the temperature dependences ρ(<i>T</i>). It is demonstrated that there is a correlation between the density of electronic states and the electrical resistivity. It is suggested that a similar relationship also exists for other electronic and magnetic properties of similar Heusler alloys, which can be used to predict their properties and to select the materials for the practical use in the field of spintronics and microelectronics.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Electrical Resistivity and Electronic Structure of (Cu1 – xCox)2MnAl Heusler Alloys upon Transition from the Cu2MnAl Ferromagnet to the Co2MnAl Topological Semimetal

  • Yu. A. Perevozchikova,
  • E. D. Chernov,
  • A. V. Lukoyanov,
  • P. B. Terentev,
  • P. S. Korenistov,
  • V. V. Chistyakov,
  • E. B. Marchenkova,
  • V. V. Marchenkov

摘要

Abstract

The temperature dependences of the electrical resistivity of five (Cu1–xCox)2MnAl (x = 0, 0.25, 0.5, 0.75, 1) Heusler alloys have been experimentally investigated at temperatures from 78 to 300 K, and calculations of the electronic structure within the framework of the density functional theory, performed for them. It is shown that upon transition from a Cu2MnAl ferromagnet to a Co2MnAl topological semimetal, the electronic structure is rearranged, thus leading to significant changes in the electrical resistivity: its value changes by more than an order of magnitude, and the curvature of its temperature dependences changes from positive to negative. The latter correlates with an increase in the partial density of the 3d states at the Fermi level, which enhances the sd interband scattering and leads to a contribution to the resistivity ρ, which is responsible for the negative curvature of the temperature dependences ρ(T). It is demonstrated that there is a correlation between the density of electronic states and the electrical resistivity. It is suggested that a similar relationship also exists for other electronic and magnetic properties of similar Heusler alloys, which can be used to predict their properties and to select the materials for the practical use in the field of spintronics and microelectronics.