Abstract
Multilayers of Ti/Fe/[Nd−Fe−B/Fe]×5/Ti/glass whose Fe layers had thicknesses ranging from 0 to 50 nm and whose Nd−Fe−B layers had thicknesses ranging from 0 to 100 nm were fabricated by RF sputtering. Magnetization measurements showed that the minor loops of almost all the multilayers exhibited spring−back behavior, which suggests exchange−coupling between the Fe and Nd−Fe−B layers. To estimate the coupling strength between the Fe and Nd−Fe−B layers, we performed a micromagnetic calculation of the magnetization curves. From a comparison of the experimental and calculated results, we can infer that the coupling strength between Fe and Nd−Fe−B layers is about 2.0×10 − 3 J/m2, which is about 10% of that in Fe/Fe and Nd−Fe−B/Nd−Fe−B couplings.
