In the disordered local moment picture, we calculated the magnetization (M) and magnetic anisotropy energy (MAE) of FePt, CoPt, and MnAl ordered alloys and a body-centered tetragonal FeCo (bct-FeCo) disordered alloy, assuming spatially fluctuated spin configurations at finite temperatures. All alloys exhibit the relation K1(T)/K1(0) = (M(T)/M(0))n with the exponent n 2. This is consistent with the two-ion anisotropy model, in contrast to the usual single-ion anisotropy model exhibiting n = 3. Because these systems have different mechanisms of MAE, we suggest that this relation is a general rule for itinerant electron systems.
ASJC Scopus subject areas
- Physics and Astronomy(all)