Magnetic Excitations of the Kondo Insulator SmB$_{6}$

ORAL

Abstract

Research within the past year indicates the long-studied Kondo insulator SmB$_{6}$ may be a topological insulator, with an insulating bulk at low temperatures and topologically protected metallic surface states. Because electron-electron interactions give rise to the insulating state, there is intense interest in SmB$_{6}$. Using time-of-flight inelastic neutron scattering, we have probed magnetic excitations over a wide range of energy and momentum transfer. Consistent with previous work there is a resonant mode near 14 meV and a broad spectrum of excitations centered near 30 meV. This data set provides a comprehensive map of the Q-dependence of the excitations throughout the Brillouin zone allowing for comparison to theoretical models describing the anomalous insulting state.

*Work at IQM was supported by the U.S. Department of Energy, office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Award DE-FG02-08ER46544. Work at ORNL was supported by LDRD 06576. PAA is supported by RFBR grant 14-02-00272

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Authors

  • Wesley Fuhrman

    • Johns Hopkins University
    • Johns Hopkins

  • Jonathan Leiner

    • Oak Ridge National Lab

  • Garrett Granroth

    • Oak Ridge National Laboratory
    • Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge TN 37830 USA
    • ORNL, TN
    • Neutron Data Analysis and Visualization Division, Oak Ridge National Laboratory
    • Oak Ridge National Lab
    • Quantum Condensed Matter Division, Oak Ridge National Laboratory

  • M.D. Lumsden

    • Oak Ridge National Lab
    • Quantum Condensed Matter Division, Oak Ridge National Laboratory

  • Pavel Alekseev

    • Kurchatov Institute

  • Jean-Michel Mignot

    • Laboratoire Leon Brillouin

  • Seyed Koohpayeh

    • Johns Hopkins University

  • Patrick Cottingham

    • Johns Hopkins University

  • William Phelan

    • Johns Hopkins University

  • Leslie Schoop

    • Department of Chemistry, Princeton University
    • Princeton University

  • Robert Cava

    • Department of Chemistry, Princeton University
    • Department of Chemistry, Princeton university, Princeton NJ 08544 USA
    • Princeton University Chemistry Department
    • Institute for Quantum Matter, Princeton University
    • Department of Chemistry, Princeton University, NJ, 08544, USA
    • Princeton University

  • Tyrel McQueen

    • Johns Hopkins University
    • Department of Chemistry, Department of Physics and Astronomy The Johns Hopkins University
    • The Johns Hopkins University

  • Collin Broholm

    • Johns Hopkins University
    • Institute for Quantum Matter, Johns Hopkins University, NIST Center for Neutron Research