Pressure-induced electronic, magnetic, half-metallic, and mechanical properties of half-Heusler compound CoCrBi

• Published in: Journal of magnetism and magnetic materials 2017-09, Vol.438, p.5-11
• Main Authors: Huang, H.M., Luo, S.J., Xiong, Y.C.
• Format: Article
• Language: English
• Subjects: Alloys; CoCrBi; Elastic constants; Elastic properties; Electron spin; Fermi level; Half-metallic properties; Heusler alloys; Heusler compound; Lattice parameters; Magnetic moments; Magnetic properties; Mathematical analysis; Mechanical properties; Stability; Studies
• ISSN: 0304-8853; 1873-4766
• DOI: 10.1016/j.jmmm.2017.04.057

[Display omitted] •CoCrBi shows half-metallic property under uniform pressure.•The half-metallic properties of CoCrBi can be obtained at the uniform pressure from 7.45 to 295GPa.•The mechanical stability of CoCrBi can be maintained at uniform pressure from 0 to 47.6GPa.•Compressing the lattice constant in one direction can realize the transition from metallic to half-metallic properties. The structural, electronic, magnetic, half-metallic and mechanical properties of half-Heusler alloy CoCrBi under pressure have been studied by first-principle calculations. CoCrBi is found to be half-metallic under the uniform pressure from 7.45 to 295GPa, and the total magnetic moment is 2.00μB per formula unit. The transitions from metal to half-metal and from half-metal to metal occur at 7.45 and 295GPa, respectively. The calculations show that the uniform pressure has an important influence on the minority-spin states, leading to a slight reconstruction of the minority-spin states with a shift of Fermi level. The calculated elastic constants revel that the mechanical instability will occur if the pressure is greater than 47.6GPa. Two kinds of tetragonal distortions under non-uniform pressure are also studied. It is found that the change of c/a ratio has no obvious influence on the electronic structures and magnetic properties, whereas, compressing the lattice constant in one direction can also realize the transition from metallic to half-metallic properties for CoCrBi.