DOMAIN WALL DYNAMICS AND EQUIVALENT CIRCUTTS IN FERROMAGNETIC MATERIALS

The study of magnetic properties of ferro and ferri-magnetic materials has shown that, due to their different time constants, magnetisation mechanisms (domain wall displacement, spin rotation and wall bulging) can be separated by using the complex permeability formalisms, they exhibit characteristic features in $\mu$′ versus $\mu$" plots. In many cases. the elements (inductances, resistances and capacitances) of the equivalent circuit representing the friquency behaviour, can also be associated with physical parameters of the sample [1-3]. In a different approach, domain wall dynamics can be represented by a motion equation with mass, damping and restoring force terms [4]. In this paper, we show that these two approaches are consistent and how they are related.