1. The electronic structure and spin polarization of Fe3−xMnxSi and Fe3−yMnSiy alloys
- Author
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Jamil M. Khalifeh, C. Demangeat, Hu-Bin Luo, Qing-Miao Hu, Bothina Hamad, and Ibrahim Abu Aljarayesh
- Subjects
Magnetic moment ,Spin polarization ,Spintronics ,Condensed matter physics ,Band gap ,Chemistry ,Supercell (crystal) ,General Physics and Astronomy ,Coherent potential approximation ,Direct and indirect band gaps ,Electronic structure - Abstract
First principle calculations using supercell approach and coherent potential approximation (CPA) are performed to investigate the electronic and magnetic structures of Fe3−xMnxSi and Fe3−yMnSiy alloys, where x,y=0, 0.25, 0.50, 0.75, 1.00, 1.25, 1.5, 1.75, and 2.25. Using supercell calculations we obtained a metallic behavior for x=0, 0.25, and 0.5 in Fe3−xMnxSi alloys with spin polarizations of 24%, 39%, and 93%, respectively. The behavior starts to be half-metallic at x=0.75 with a small direct band gap that increases for higher concentrations of Mn. Among the half-metallic systems, only those of L21 structure at x=1 and 2 possess indirect band gaps along Γ-X symmetry line. The change of Si concentration in Fe3−yMnSiy structures retrieve the metallic behavior for all concentrations except y=1.25 that shows a half-metallic behavior with a direct band gap of 0.27 eV. We obtained a good agreement between supercell and CPA calculations for the values of the magnetic moment and the trends of the formation ene...
- Published
- 2010