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arXiv · 1701.06584

Determination of Hund's coupling in 5d Oxides using Resonant Inelastic X-ray Scattering

Bo Yuan·J. P. Clancy·A. M. Cook·C. M. Thompson·J. Greedan·G. Cao·B. -C. Jeon·T. -W. Noh·M. H. Upton·D. Casa·T. Gog·Arun Paramekanti·Young-June Kim
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Abstract

We report resonant inelastic X-ray scattering (RIXS) measurements on ordered double perovskite samples containing Re$^{5+}$ and Ir$^{5+}$ with $5d^2$ and $5d^4$ electronic configurations respectively. In particular, the observed RIXS spectra of Ba$_2$YReO$_6$ and Sr$_2$MIrO$_6$ (M=Y, Gd) show sharp intra-t$_{2g}$ transitions, which can be quantitatively understood using a minimal `atomic' Hamiltonian incorporating spin-orbit coupling ($\lambda$) and Hund's coupling ($J_H$). Our analysis yields $\lambda=0.38(2)$eV with $J_H=0.26(2)$eV for Re$^{5+}$, and $\lambda=0.42(2)$eV with $J_H=0.25(4)$eV for Ir$^{5+}$. Our results provide the first sharp estimates for the Hund's coupling in $5d$ oxides, and suggest that it should be treated on equal footing with spin-orbit interaction in multi-orbital $5d$ transition metal compounds.

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Bo Yuan, J. P. Clancy, A. M. Cook, C. M. Thompson, J. Greedan, G. Cao, B. -C. Jeon, T. -W. Noh, M. H. Upton, D. Casa, T. Gog, Arun Paramekanti, Young-June Kim. 2017-01-23. Determination of Hund's coupling in 5d Oxides using Resonant Inelastic X-ray Scattering. https://doi.org/10.1103/physrevb.95.235114

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