Eur. Phys. J. B (2017) 90: 64
https://doi.org/10.1140/epjb/e2017-70729-0

Regular Article

Influence of Si substitution on structural, electronic and magnetic properties of Fe₂MnGa Heusler compound

¹ Jiangsu Key Lab on Opto-Electronic Technology, School of Physics and Technology, Nanjing Normal University, Nanjing 210023, P.R. China
² Department of Physics, Nanjing University of Information Science Technology, Nanjing 210044, P.R. China

^a e-mail:jsnjwangl@163.com

Received: 11 December 2016
Received in final form: 14 February 2017
Published online: 10 April 2017

Abstract

We investigate the electronic and magnetic properties of Fe₂MnGa_1−xSi_x alloy (x = 0, 0.25, 0.5, 0.75, and 1) using first-principles density functional theory within the generalized gradient approximation method. The lattice constant decreases linearly whereas bulk modulus increases with increasing Si content. The total magnetic moment varies linearly with increasing Si content, which follows the Slater-Pauling rule. Electronic band structure calculations indicate that the Fe₂MnGa_1−xSi_x exhibits half-metallic character for all the concentrations studied and the spin polarization and the spin-down band gap both increase with the Si content. Based on the magnetic properties calculations, the Heisenberg exchange coupling parameters give Fe-Mn ferromagnetic coupling and Mn-Mn antiferromagnetic coupling. The T_C first decreases and then increases with Si content, which is in well agreement with the experimental results.