An eddy-current and micromagnetism model with applications to disk write heads

As data rates increase and the size of the disk write head decreases it is likely that a standard non-linear eddy-current simulation of a disk write head will not fully capture dynamic effects. In this paper we propose a coupled eddy-current and micromagnetics model for the disk write head. We present a simple finite difference formulation derived from a mass-lumped finite element method. This derivation allows us to verify that, before time discretization, the semi-discrete scheme obeys the same energy decay equality as the partial differential equation model. We show some numerical results for an 'academic' disk writer model. Copyright (C) 2004 John Wiley Sons, Ltd.