Physics

Magnetocrystalline anisotropy calculation of Fe-Ga alloys by the magnetic torque method

M. V. Matyunina^a, M. A. Zagrebin^ab, V. V. Sokolovskiy^ba, V. D. Buchel'nikov<sup>ab

a</sup> Chelyabinsk State University, Chelyabinsk, Russia
^b National University of Science and Technology MISIS, Moscow

Abstract: The magnetic properties of body-centered cubic structures of Fe$_{100-x}$Ga$_x$ were investigated using the density functional theory. The dependence of the magnetocrystalline anisotropy (MCA) energy as a function of the tetragonal distortions was obtained by the help of the magnetic torque method implemented in the SPR-KKR software package. The dependence of MCA energy on the strain is linear and has a positive slope for a disordered A2 phase and a partially ordered B2 one. For ordered D0$_3$ structure, this dependence demonstrates a complex nonlinear behavior. The B2 phase makes the main contribution to tetragonal magnetostriction in the region of concentrations $21 \leq x \leq 25$ at.%. The shear modulus obtained using the SPR-KKR software package decreases with increasing Ga concentration.

Keywords: magnetic torque method, magnetocrystalline anisotropy energy, magnetostriction, shear modulus.

UDC: 537.634

Received: 10.05.2020
Revised: 25.05.2020

DOI: 10.24411/2500-0101-2020-15204