The stress-induced anisotropy in the (110) plane of the magnetostrictive TbDyFe [110] oriented crystal

The magnetostriction curve of [110]-oriented Tb0.3Dy0.7Fe1.9 crystal is measured under different compressive prestress. It is observed that the saturation magnetostriction keeps on increasing with the increase in compressive prestress from 0 to 75 MPa. The distribution of the free energy within the (110) plane normal to the stress axis is calculated to clarify the enhancement of saturation magnetostriction under large compressive prestress. It is found that with the increase in the prestress, the lowest energy positions deviate from the initial four ⟨111⟩ easy axes in the (110) plane, approaching the [11¯0] and [1¯10] orientations. The stress-induced anisotropy results in the change in initial domain configuration and further the enhancement of saturation magnetostriction, which well explains the experimental results.