Modelling of rhombohedral magnetostriction in Fe-Ga alloys

The paper presents the results of modelling of rhombohedral magnetostriction for Fe-Ga alloys in the cubic crystal structures. The results are obtained with the help of the theory of density functional. We show that the energy of magnetic crystalline anisotropy is a decreasing function of the small deformation in the concentration range from 3,125 to 25 at.%. Magnetic crystalline anisotropy changes the sign, if the deformation is more than 1% for alloys with Ga 15,625, 21,875 and 25 at.%. Rhombohedral magnetostriction constant agrees well with the experiment results for alloys with Ga concentration at 12,5 - 18,75 at.%.