NUMERICAL INVESTIGATION OF 90-DEGREES COUPLING IN MAGNETIC SANDWICHES- THERMAL VARIATION, INFLUENCE OF ANISOTROPY

Evidence for 90-degrees coupling between Fe layers in epitaxial Fe/NM/ Fe sandwiches (NM = Cr, Au, Al) has recently been reported by various groups. Following Slonczewski's approach, we interpret this 90-degrees coupling as arising from spatial nanoscopic fluctuations in the inter layer coupling through the NM spacer layer. We investigate numerically a model based on this assumption. The magnetization curves and coupli ng energy have been calculated in the realistic situation where thin N M and Fe layers are deposited on a thick Fe whisker. We investigate in particular the role of the magnetocrystalline anisotropy in the prope rties of this 90-degrees coupling. We also compare the thermal variati on of the bilinear coupling (A12) with that of the 90-degrees coupling .