Ground-State-Moment-Analysis: A quantitative tool for X-ray magnetic circular dichroism analysis for <Emphasis Type="Italic">3d</Emphasis> transition metals

By the use of sum rules and X-ray magnetic circular dichroism (XMCD) integral spectral values, experimentally determined element specific spin- and orbital-magnetic moments could be extracted. Therefore, sum rules neglect all additional spectral shape information. On the basis of so called ground state moments and their spectral representations, XMCD spectra could be fitted. The gain of information due to this method is directly related to the analysis of the spectral shape. Simple and complex spectra, with many different observable spectral features, could be quantitatively analyzed. Different unoccupied parts of the bandstructure have been resolved and intuitively interpreted by the moment analysis procedure. Focusing on this fitting method, we will review recent applications to Iron-Garnets and CrO₂ and show new results for Fe-, Mn-, and V-L_2,3 XMCD spectra. In addition, spectral overlap between the L₂ and L₃ edges at the light transition metal site could be handled by this method, and quantitative magnetic moments have been extracted from the spectra. This is the basis for a possible future element specific renormalization technique, used for the whole series of the transition metals, which is very important at the light transition metal site. PACS 87.64.Ni; 75.70.-i; 75.50.Cc; 75.70.Ak