Video of the seminar by Rachel Nickel: "Shedding Light on Electronic and Magnetic Order: XAS and RIXS at ID32"
Rachel Nickel gave this seminar on the 17th of November of 2025, hosted by Martí Gich (NN group):
Abstract
Mankind has used the magnetic and electronic properties of materials to transform the world. Our knowledge of these properties and their integration into technology has been enabled by the advancement of both experimental techniques and theoretical models. One particularly notable innovation was the development of synchrotron radiation sources in the late 20th century. These x-ray facilities provide brilliant sources of x-rays with both energy and polarization tunability, which continue to illuminate new physics and chemistry.
In this talk I will present an introduction to the two soft x-ray spectroscopic techniques performed at ID32 of the European Synchrotron Radiation Facility: x-ray absorption spectroscopy (XAS) and resonant inelastic x-ray scattering (RIXS). These methods are critical to the study of magnetism and electronic structure because they provide element- and site-specific information about the 3d and 4f valence electrons in transition metals and rare earths, respectively. Furthermore, the polarization dependence of the measured spectra (dichroism) depends on the distribution of charge and spin. This means that both XAS and RIXS can provide insight into electronic and magnetic ordering. However, as a photon-in photon-out technique RIXS is much more powerful. Its ability to measure the energy and momentum transfer of excitations gives a richer picture of the material than XAS. Overall, I will discuss the advantages and limitations of both techniques, highlighting recent work and some of the unique capabilities of ID32.
Short bio
Rachel Nickel is a post-doctoral fellow at ID32 of the European Synchrotron Radiation Facility. She received a PhD in condensed matter physics in 2024 from the University of Manitoba (Canada) where she was a Vanier Scholar. Though her research is now focused on the phase transitions of magnetic materials, her past projects have ranged from bacteria to batteries. She is interested in expanding the synchrotron user community and believes there are valuable techniques available for all areas of research.
