Study of dynamic process of domain change in the stepped giant magnetoimpedance element

A giant magnetoimpedance (GMI) element with stepped impedance property was reported for rectangular amorphous soft magnetic thin film with an in-plane uniaxial easy axis in a controlled direction. This stepped change of impedance occurs simultaneously with a change in a magnetic domain, and its physical basis was explained as the intersection of the level of magnetic energy in each case of these domain structures. In this paper, an induced pulse-voltage caused by a non-linear leap of magnetization in the domain change is studied, for the purpose of making dynamics of the domain change clear. We report the results of detecting a pulse signal by using a planar coil fabricated with the stepped GMI element. Some fundamental properties of the pulse signal are also reported, such as its form, and variations in its height as a function of the frequency of the external magnetic field. As a result we found that the domain change in the stepped GMI element is a kind of Barkhausen jump.