Separate quantitative evaluation of degree of order and perpendicular magnetic anisotropy for disorder and order portion in FePt granular films

The dependence of the degree of order and perpendicular magnetic anisotropy (KuâŠ1) on magnetic layer thickness (dmag) for FePt granular films with various grain boundary materials (GBMs) were investigated. According to the analysis for granular films with a constant GBM volume of 30 vol%, the order, disorder, and non-epitaxial portions co-existed in the FePt granular films. From the separate quantitative evaluation for these portions, the following was found; 1) the degree of order and magnitudes of KuâŠ1 for disorder and order portions against dmag were constant, while the film average evaluation resulted in the dependence of the degree of order and KuâŠ1 on dmag and the positive correlation between the grain diameter and the degree of order, 2) for the order portion, KuâŠ1 had linear correlation with the degree of order, 3) the magnitude of KuâŠ1 and the degree of order for the order portion depended on GBM.