A Resonant Inelastic X-ray Scattering investigation of the 4<i>f</i> states in SmB<sub>6</sub>

ORAL

Abstract

The crystal-field (CF) splitting of the 6H5/2 Hund's rule ground state of Sm3+ in the strongly correlated topological insulator1,2 SmB6 has been determined with high resolution resonant inelastic x-ray scattering (RIXS) at the Sm M5 edge3. The valence selectivity of RIXS allows to isolate the crystal-field-split excited multiplets of the Sm3+ (4f5) configuration from those of Sm2+ (4f6) in intermediate valent SmB6. We find that the quartet Γ8 ground state4 and the doublet Γ7 excited state are split by Δ=20meV±10meV. Considering this as an upper limit for the 4f bandwidth points to an extremely large mass renormalization from the band structure value, which can be linked to the small coefficient of fractional parentage for the hopping of the 4f electrons5. The tiny band width complies with the small value of the gap and may be used to put constraints to the energies of the topological surface states.
[1] M. Dzero et al, PRL 104, 106408 (2010)
[2] T. Takimoto, J. Phys. Soc. Jpn. 80, 123710 (2011)
[3] A. Amorese et al, PRB 100, 241107(R) (2019)
[4] M. Sundermann et al, PRL 120, 016402 (2018)
[5] G. Sawatzky & R. Green, edt. E. Pavarini & E. Koch (FZ Julich), 1.1 (2016), in Quantum Materials: Experiments and Theory

*We acknowlege financial support of DFG under grant SE-1441/4-1

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Presenters

  • Andrea Amorese

    • Max Planck Institute for Chemical Physics of Solids
    • Max Planck Institute for Chemical Physics of Solids (Dresden, Germany)

Authors

  • Andrea Amorese

    • Max Planck Institute for Chemical Physics of Solids
    • Max Planck Institute for Chemical Physics of Solids (Dresden, Germany)

  • Oliver Stockert

    • Max Planck Institute for Chemical Physics of Solids (Dresden, Germany)

  • Kurt Kummer

    • European Synchrorton Radiation Facility (Grenoble, France)
    • European Synchrotron Radiation Facility, France

  • Nicholas B Brookes

    • European Synchrorton Radiation Facility (Grenoble, France)

  • Dae-Jeong Kim

    • Department of Physics and Astronomy, University of California
    • University of California, Irvine (USA)

  • Zachary Fisk

    • University of California, Irvine (USA)

  • Maurits Wim Haverkort

    • Institute for Theoretical Physics, Heidelberg University
    • Heidelberg University
    • Institute for theoretical Physics, Heidelberg University (Germany)
    • Institute for theoretical Physics, University of Heidelberg

  • Peter Thalmeier

    • Max Planck Institute for Chemical Physics of Solids (Dresden, Germany)

  • Liu Tjeng

    • Max Planck Institute for Chemical Physics of Solids
    • Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
    • Max Planck Institute for Chemical Physics of Solids (Dresden, Germany)
    • Max Planck Institute for Chemical Physics of Solids (MPI CPfS)
    • Max-Planck Institute for Chemical Physics of Solids

  • Andrea Severing

    • Institute of Physics II, University of Cologne
    • Intitute of Physics II, University of Cologne
    • University of Cologne
    • Institute of Physics II, University of Cologne (Germany)
    • Institute of Physics II, University of Cologne, Cologne, Germany