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arXiv · 1812.08689

Spin and orbital dynamics through the metal-to-insulator transition in Cd$_2$Os$_2$O$_7$ probed with high-resolution RIXS

J. G. Vale·S. Calder·N. A. Bogdanov·C. Donnerer·M. Moretti Sala·N. R. Davies·J. Yamaura·Z. Hiroi·D. Mandrus·J. van den Brink·A. D. Christianson·D. F. McMorrow
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Abstract

High-resolution resonant inelastic x-ray scattering (RIXS) measurements ($Δ$E = 46 meV) have been performed on Cd$_2$Os$_2$O$_7$ through the metal-to-insulator transition (MIT). A magnetic excitation at 125 meV evolves continuously through the MIT, in agreement with recent Raman scattering results, and provides further confirmation for an all-in, all-out magnetic ground state. Asymmetry of this feature is likely a result of coupling between the electronic and magnetic degrees of freedom. We also observe a broad continuum of interband excitations centered at 0.3 eV energy loss. This is indicative of significant hybridization between Os 5$d$ and O 2$p$ states, and concurrent itinerant nature of the system. In turn, this suggests a possible break down of the free-ion model for Cd$_2$Os$_2$O$_7$.

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J. G. Vale, S. Calder, N. A. Bogdanov, C. Donnerer, M. Moretti Sala, N. R. Davies, J. Yamaura, Z. Hiroi, D. Mandrus, J. van den Brink, A. D. Christianson, D. F. McMorrow. 2020-01-13. Spin and orbital dynamics through the metal-to-insulator transition in Cd$_2$Os$_2$O$_7$ probed with high-resolution RIXS. https://doi.org/10.1103/physrevb.101.014441

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