Half-metallic magnetism in Ti3Co5-xFexB2

Authors

Rohit Pathak, Indian Institute of Technology
Imran Ahamed, Indian Institute of Technology
W. Y. Zhang, University of Nebraska-Lincoln
Shah Vallopilly, University of Nebraska-Lincoln
D. J. Sellmyer, University of Nebraska-LincolnFollow
Ralph Skomski, University of Nebraska-LincolnFollow
Arti Kashyap, Indian Institute of Technology

Date of this Version

2-8-2017

Citation

055713-2 Pathak et al. AIP Advances 7, 055713 (2017) Page 1-6

Comments

© 2017 Author(s).

Abstract

Bulk alloys and thin films of Fe-substituted Ti₃Co₅B₂ have been investigated by first-principle density-functional calculations. The series, which is of interest in the context of alnico magnetism and spin electronics, has been experimentally realized in nanostructures but not in the bulk. Our bulk calculations predict paramagnetism for Ti₃Co₅B₂, Ti₃Co₄FeB₂ and Ti₃CoFe₄B₂, whereas Ti₃Fe₅B₂ is predicted to be ferromagnetic. The thin films are all ferromagnetic, indicating that moment formation may be facilitated at nanostructural grain boundaries. One member of the thin-film series, namely Ti₃CoFe₄B₂, is half-metallic and exhibits perpendicular easy-axis magnetic anisotropy. The half-metallicity reflects the hybridization of the Ti, Fe and Co 3d orbitals, which causes a band gap in minority spin channel, and the limited equilibrium solubility of Fe in bulk Ti₃Co₅B₂ may be linked to the emerging half metallicity due to Fe substitution.