Propagating Spin-Orbit Excitons in a Correlated Metal

ORAL

Abstract

The presence of strong spin-orbit coupling (SOC) can lead to highly exotic phases of matter in quantum materials. While SOC is considered as a dominant energy scale in 5d compounds such as Sr2IrO4, its strength decreases for lighter elements and its significance in shaping the electronic structure of 4d materials is a topic of active debate. Here, we present a comprehensive study of the solid-solution Sr2Rh1-xIrxO4, which is situated between the 4d-electron metal Sr2RhO4 and the 5d-electron Mott insulator Sr2IrO4. We investigate the evolution of the low-energy electronic structure in the substitution series using resonant inelastic x-ray scattering and Raman spectroscopy. A focus of our study is Sr2RhO4, where we detect similar spin-orbit entangled excitations as previously observed in Sr2IrO4, albeit on a smaller energy scale and with an opposite dispersion, which we rationalize in terms of the distinct ground states of the two materials. Our findings shed new light on the role of SOC in 4d compounds and we comment on the prospects of using cation substitution as a platform to tune the effective spin-orbit interaction strength.

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Publication: V. Zimmermann et al. [submitted]

Presenters

  • Valentin L Zimmermann

    • Max-Planck-Insitute for Solid State Research

Authors

  • Valentin L Zimmermann

    • Max-Planck-Insitute for Solid State Research

  • Lichen Wang

    • Max-Planck-Institute for Solid State Research

  • Arvind K Yogi

    • UGC-DAE Consortium for Scientific Resear

  • Huimei Liu

    • IFW - Dresden

  • Deniz Wong

    • Helmholtz-Zentrum Berlin fuer Materialien und Energie

  • Christian Schulz

    • Helmholtz-Zentrum Berlin fuer Materialien und Energie

  • Maciej Bartkowiak

    • Helmholtz-Zentrum Berlin fuer Materialien und Energie

  • Klaus Habicht

    • Helmholtz-Zentrum Berlin fuer Materialien und Energie

  • Pascal Puphal

    • Max Planck Institute for Solid State Research
    • Max-Planck-Institute for Solid State Research

  • Masahiko Isobe

    • Max Planck Institute for Solid State Research
    • Max-Planck-Institute for Solid State Research

  • Matteo Minola

    • Max-Planck-Institut für Festkörperforschung
    • Max Plank Institute for Solid State Research
    • Max-Planck-Institute for Solid State Research

  • Giniyat Khaliullin

    • Max Planck Institute for Solid State Research
    • Max-Planck-Institute for Solid State Research

  • Bernhard Keimer

    • Max Planck Institute for Solid State Physics
    • Max Planck Institute for Solid State Research
    • Max-Planck-Institute for Solid State Research

  • Matthias Hepting

    • Max Planck Institute for Solid State Research
    • Max-Planck-Institute for Solid State Research
    • Max Planck Institute for Solid State Physics, FRG