X-ray magnetic circular dichroism — a universal tool for magnetic investigations

In this paper, we will emphasize that XMCD is a universal tool for studies of magnetism with atomic sensitivity. A quantitative analysis of spin and orbital momenta is possible, which could be extracted using sum rules developed by Thole and Carra. For magnetic investigations, it is possible to measure atomic hysteresis loops with high resolution. We will also show that it is feasible to study quantitatively magnetocrystalline anisotropy in complex magnetic structures and to understand their microscopic origin in terms of projected orbital momentum distributions and spin–orbit coupling. We demonstrate that a cubic like anisotropy is present in the colossal magneto resistance Lanthanummanganates. This could be quantitatively addressed to changes in the measured projected orbital moments. In addition, a cubic like anisotropy was observed in oxygen K edge XMCD hysteresis loops. It is also possible to measure quantitatively site selective magnetization profiles in multilayer systems. Therefore, we have developed a magnetic specular hard X-ray diffraction technique. Using the Parratt algorithm, we could extract the platinum L3 moment magnetization profile as a function of distance to a ferromagnetic cobalt thin layer.