Affiliation: ALBA Synchrotron Light Source, Barcelona, Spain

Research Field: Electronic and magnetic ground state of spin-orbit active transition metal compounds using x-ray spectroscopy (XAS, XMCD, RIXS)

Introduction to x-ray absorption spectroscopy and x-ray magnetic circular dichroism

The lecture will first provide a general introduction to the absorption process and the methods used to measure an x-ray absorption spectrum (XAS). I will present the key features that makes this technique so powerful and simple examples of the variety of information about the local electronic and magnetic structure that can be determined from XAS. In the second part I will discuss the spectral shape of XAS and the need of a multielectron approach to describe it. Finally, I will explain the application of the sum rules to x-ray magnetic circular dichroism (XMCD) data in order to determine the spin and orbital moments. Examples of experimental studies using XMCD will be shown.