DEPENDENCE OF COERCIVITY ON THE MEASUREMENT METHOD IN EPITAXIAL MAGNETIC GARNET-FILMS

The coercivity of epitaxial magnetic garnet films is investigated by different measurement methods. On eliminating the influence of the neighboring domains the domain wall oscillating method, measuring the start field of wall displacement, i.e., the domain wall coercivity, was found to be the best means of characterizing the domain wall-defect interaction. Coercivities determined by domain expansion, bubble translation and from hysteresis measurements are significantly higher than the domain wall coercivity. Empirical correlation was found between the results of these latter methods, but no correlation was found with domain wall coercivity.