We present a study of resonant inelastic X-ray scattering (RIXS) spectra collected at the rare-earth L edges of divalent hexaborides YbB6 and EuB6. In both systems, RIXS-active features are observed at two distinct resonances separated by ∼10 eV in incident energy, with angle-dependence suggestive of distinct photon scattering processes. RIXS spectra collected at the divalent absorption peak strongly resemble the unoccupied 5d density of states calculated using density functional theory, an occurrence we ascribe to transitions between weakly-dispersing 4f and strongly dispersing 5d states. In addition, anomalous resonant scattering is observed at higher incident energy, where no corresponding absorption feature is present. Our results suggest the far-reaching utility of L-edge RIXS in determining the itinerant-state properties of f-electron materials.
@article{arxiv.1905.09862,
title = {Exploring itinerant states in divalent hexaborides using rare-earth $L$ edge resonant inelastic X-ray scattering},
author = {Donal Sheets and Vincent Flynn and Jungho Kim and Mary Upton and Diego Casa and Thomas Gog and Zachary Fisk and Maxim Dzero and Priscilla F. S. Rosa and Daniel G. Mazzone and Ignace Jarrige and Jian-Xin Zhu and Jason Hancock},
journal= {arXiv preprint arXiv:1905.09862},
year = {2020}
}