Induced magnetic polarization in Cu layers of Gd/Cu multilayers studied by X-ray magnetic circular dichroism

The induced magnetic polarization in nonmagnetic layers and its relationship with the magnetization in ferromagnetic layers are investigated for Gd/Cu multilayers with X-ray magnetic circular dichorism (XMCD). The XMCD measurements show that the peak intensities at the Cu K-edge decrease in proportion to those at the Gd L(3)(-)edge as the temperature increases. The overall shape of the XMCD spectra at the Cu K-edge, on the other hand, does not change. These results suggest that the size of the magnetic polarization in the Cu layers changes but the depth profile remains unchanged when the Gd magnetization varies in size. The XMCD spectra at the Cu K-edge are composed of several positive and negative peaks. A possible origin of the specific shape of the spectra is discussed.