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 insulator SmB6 [1,2] has been determined with high resolution resonant inelastic x-ray scattering (RIXS) at the Sm M5 edge [3]. 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 G8 ground state [4] and the doublet G7 excited state are split by DCF=20±10meV. Considering this as an upper limit for the 4f bandwidth suggests 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 electrons [5]. 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, arXiv:1901.10808v2
[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

*Financial support of the DFG under grant SE-1441/4-1 is acknowledged

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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

  • Kurt Kummer

    • European Synchrotron Radiation Facility

  • Nicholas B Brookes

    • European Synchrotron Radiation Facility

  • Dae-Jong Kim

    • Department of Physics and Astronomy, University of California, Irvine

  • Zachary Fisk

    • Department of Physics and Astronomy, University of California Irvine
    • Department of Physics and Astronomy, University of California, Irvine
    • Dept. of Physics and Astronomy, University of California Irvine
    • University of California, Irvine, USA
    • Department of Physics and Astronomy,, University of California-Irvine

  • Maurits Haverkort

    • Institute for Theoretical Physics, Heidelberg University
    • Institute for theoretical physics
    • Institute of Theoretical Physics, University of Heidelberg
    • Theoretical Physics, Heidelberg University, Germany
    • Heidelberg University

  • Peter Thalmeier

    • Max Planck Institute for Chemical Physics of Solids

  • Liu Hao Tjeng

    • Max Planck Institute for Chemical Physics of Solids

  • Andrea Severing

    • Institute of Physics II, University of Cologne
    • Physics 2, University of Cologne, Germany
    • University of Cologne