Landau-Lifshitz magnetization dynamics and eddy currents in metallic thin films

An analytical technique is presented to predict the magnetization dynamics in metallic thin films subjected to a dc magnetic field perpendicular to the film plane and a circularly polarized rf field in the film plane. By neglecting exchange effects, an approximate dynamic equation is derived in which the description of magnetization dynamics within the film is formally reduced to the study of an equivalent nonconducting uniformly magnetized system characterized by an effective damping constant also including the effect of eddy currents. Under this approximation, known results about uniform magnetization modes in nonconducting systems can be applied and analytical expressions are derived for the nonuniform magnetization in the film. The conditions yielding instabilities in the film response are discussed. The approximate analytical predictions are compared with the results of numerical simulations. (C) 2002 American Institute of Physics.