Resonant inelastic x-ray scattering in warm-dense Fe compounds beyond the SASE FEL resolution limit
Communications Physics Nature Research 7:1 (2024) 266
Authors:
Alessandro Forte, Thomas Gawne, Karim K Alaa El-Din, Oliver S Humphries, Thomas R Preston, C茅line Cr茅pisson, Thomas Campbell, Pontus Svensson, Sam Azadi, Patrick Heighway, Yuanfeng Shi, David A Chin, Ethan Smith, Carsten Baehtz, Victorien Bouffetier, Hauke H枚ppner, Alexis Amouretti, David McGonegle, Marion Harmand, Gilbert W Collins, Justin S Wark, Danae N Polsin, Sam M Vinko
Abstract:
Resonant inelastic x-ray scattering (RIXS) is a widely used spectroscopic technique, providing access to the electronic structure and dynamics of atoms, molecules, and solids. However, RIXS requires a narrow bandwidth x-ray probe to achieve high spectral resolution. The challenges in delivering an energetic monochromated beam from an x-ray free electron laser (XFEL) thus limit its use in few-shot experiments, including for the study of high energy density systems. Here we demonstrate that by correlating the measurements of the self-amplified spontaneous emission (SASE) spectrum of an XFEL with the RIXS signal, using a dynamic kernel deconvolution with a neural surrogate, we can achieve electronic structure resolutions substantially higher than those normally afforded by the bandwidth of the incoming x-ray beam. We further show how this technique allows us to discriminate between the valence structures of Fe and Fe2O3, and provides access to temperature measurements as well as M-shell binding energies estimates in warm-dense Fe compounds.
