Thermally activated magnetization reversal through multichannels

Magnetization reversal of an isolated single-domain particle through multichannels was analytically studied. Results for a dichotomic channel of barriers demonstrate that the dynamical reversal process shows a multiexponential relaxation. At low attempting rate, the magnetization encounters a nearly static barrier, and at high attempting rate, it relaxes through an average of barrier heights. For the intermediate attempting rate, the magnetization usually relaxes multiexponentially, but only one relaxation time remains dominated at the low temperature. (C) 1997 American Institute of Physics.