Dipolar mechanism for magnetostriction in amorphous ferrimagnetic alloys

Magnetoelastic interactions in amorphous rare earth-3d transition metal thin films are analysed. The calculations are based on the anisotropic pair ordering model. Pair energy is expressed in the pseudodipolar form. It has been shown that magnetoelastic tensor consists of two parts:isotropic and anisotropic. The case, when pair energy has the form of classical magnetic dipolar interaction is considered in details. For such case the isotropic part of magnetoelastic energy vanishes. Simple expressions have been derived for magnetostriction constants. In frames of presented theory the volume magnetostriction has nonzero value.