Modeling of torsion stress giant magnetoimpedance in amorphous wires with negative magnetostriction

摘要

A model describing the influence of torsion stress on the giantmagnetoimpedance in amorphous wires with negative magnetostriction is proposed.The wire impedance is found by means of the solution of Maxwell equationstogether with the Landau-Lifshitz equation, assuming a simplified spatialdistribution of the magnetoelastic anisotropy induced by the torsion stress.The impedance is analyzed as a function of the external magnetic field, torsionstress and frequency. It is shown that the magnetoimpedance ratio torsiondependence has an asymmetric shape, with a sharp peak at some value of thetorsion stress. The calculated field and stress dependences of the impedanceare in qualitative agreement with results of the experimental study of thetorsion stress giant magnetoimpedance in Co-based amorphous wires.