Influence of Defects Shape and Period on Domain Wall Coercive Field

Abstract

Results of calculation of the domain wall coercive field, H _CW , as a function of the domain wall width parameter, $\delta = \sqrt {{A/K}}$, (A — exchange constant, K — anisotropy constant) and of the material defect characteristic period, d, are presented. Unlike in many previously published models it is shown that there is no prominent maximum on the H _CW (d/δ) dependence as long as δ and the shape of the defects are kept constant. A prominent maximum at the H _CW (d/δ) dependence can be observed, however, if δ is changed and d is kept constant. The drop of H _CW (d/δ) for large values of the argument, is connected with δ to be comparable with size of the single defect and it is conditioned by the specific defect shape.