Magnetization dynamics in metallic thin films

The Landau-Lifshitz-Gilbert equation for the magnetization coupled with Maxwell equations for the eddy current field is studied in metallic thin films. The field excitation considered is a constant field h(a2) superimposed to a time varying component h(a perpendicular to) rotating in the perpendicular plane of the film. In the limit in which exchange interactions are neglected and dissipation is low an approximated picture is obtained, in which intrinsic plus eddy current dissipation effects are described by an effective z-dependent damping constant increasing from the minimum value at the surface to the maximum value at the film center. Approximate solutions for the film magnetic response are obtained and their stability is discussed by comparing the phase portraits of the dynamics associated with different depths I inside the film. (C) 2001 Elsevier Science B.V. All rights reserved.