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arXiv · 1905.09862

Exploring itinerant states in divalent hexaborides using rare-earth $L$ edge resonant inelastic X-ray scattering

Donal Sheets·Vincent Flynn·Jungho Kim·Mary Upton·Diego Casa·Thomas Gog·Zachary Fisk·Maxim Dzero·Priscilla F. S. Rosa·Daniel G. Mazzone·Ignace Jarrige·Jian-Xin Zhu·Jason Hancock
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Abstract

We present a study of resonant inelastic X-ray scattering (RIXS) spectra collected at the rare-earth $L$ edges of divalent hexaborides YbB$_6$ and EuB$_6$. In both systems, RIXS-active features are observed at two distinct resonances separated by $\sim10$ 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 5$d$ density of states calculated using density functional theory, an occurrence we ascribe to transitions between weakly-dispersing 4$f$ and strongly dispersing 5$d$ 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.

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Donal Sheets, Vincent Flynn, Jungho Kim, Mary Upton, Diego Casa, Thomas Gog, Zachary Fisk, Maxim Dzero, Priscilla F. S. Rosa, Daniel G. Mazzone, Ignace Jarrige, Jian-Xin Zhu, Jason Hancock. 2019-05-23. Exploring itinerant states in divalent hexaborides using rare-earth $L$ edge resonant inelastic X-ray scattering. https://doi.org/10.1088/1361-648x/ab5e0f

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