Correlation between fractal dimension and reversal behavior of magnetic domain in Co/Pd nanomultilayers

Abstract

We report the experimental finding that there is a close correlation between fractal geometry and reversal mechanism of magnetic domain in Co/Pd nanomultilayers. We have measured the fractal dimension D-f of magnetic domain as well as the wall-motion speed V, the nucleation rate R, and the reversal ratio V/R in Co/Pd nanomultilayer films during magnetization reversal via time-resolved direct domain observation. Interestingly enough, D-f is inversely related to the reversal ratio V/R, which could be quantitatively explained using a micromagnetic simulation based on thermally activated relaxation model. We find that the fractal dimension is a crucial parameter to characterize magnetization reversal behavior as well as jaggedness of domain geometry. (C) 2003 American Institute of Physics.