ELEMENT-SPECIFIC CURIE TEMPERATURES OF NI CU/CO TRILAYERS/

In order to improve our understanding of the magnetism of 3d-multilaye rs the following questions are of interest: How does a nonmagnetic cap or spacer layer, like Cu, influence the magnetism of 3d ferromagnetic films? How does the ferromagnetic order of one layer (i.e. Ni) influe nce another (i.e. Co) via a spacer? Using magnetic circular X-ray dich roism Co/Ni, Cu/Co and Cu/Ni bilayers and Co/Cu/Ni and Ni/Cu/Co trilay ers grown on a Cu(0 0 1) substrate were investigated. After having bee n covered by 2-7 ML Cu, Ni and Co films exhibit a significantly lower T-c. For trilayers different Curie temperatures were determined for Ni and Co when separated by a 2-6 ML Cu spacer. The coupling of Ni and C o layers was found to be both ferromagnetic and antiferromagnetic, dep ending on the spacer thickness and the sequence of the layers. (C) 199 8 Elsevier Science B.V. All rights reserved.