Spin and orbital excitations through the metal-to-insulator transition in Cd2Os2O7 probed with high-resolution resonant inelastic x-ray scattering

High-resolution resonant inelastic x-ray scattering measurements (ΔE=46meV) have been performed on Cd2Os2O7 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 the 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 5d and O 2p states and the concurrent itinerant nature of the system. In turn, this suggests a possible breakdown of the free-ion model for Cd2Os2O7.