Observation of two-dimensional Fermi surface and Dirac dispersion in the new material YbMnSb$_2$

ORAL

Abstract

We present the synthesis, crystal structure, electronic structure, and transport properties of the new material YbMnSb$_2$. Our measurements reveal that this system is a low-carrier-density semimetal with a 2D Fermi surface arising from a 3D Dirac dispersion. This Fermi surface is consistent with the predictions of antiferromagnetic density functional theory calculations and the Fermi surface observed via angle-resolved photoemission spectroscopy. The quantitative agreement between these measurements and calculations indicates that YbMnSb$_2$ may be a new topological semimetal in the presence of magnetic order.

*R. K. is supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1106400. C. J., J. G. A., and much of this work received support from the Gordon and Betty Moore Foundation Grant No. GBMF4374.

–

Authors

  • Robert Kealhofer

    • Department of Physics, University of California, Berkeley, and Lawrence Berkeley National Laboratory

  • Sooyoung Jang

    • Department of Physics, University of California, Berkeley, and Lawrence Berkeley National Laboratory

  • Sinead Griffin

    • Department of Physics, University of California, Berkeley, and Lawrence Berkeley National Laboratory

  • Caolan John

    • Department of Physics, University of California, Berkeley, and Lawrence Berkeley National Laboratory

  • Spencer Doyle

    • Department of Physics, University of California, Berkeley, and Lawrence Berkeley National Laboratory

  • Jeffrey Neaton

    • Department of Physics, University of California, Berkeley
    • Department of Physics, University of California, Berkeley, and Lawrence Berkeley National Laboratory

  • James Analytis

    • University of California, Berkeley
    • Department of Physics, University of California, Berkeley, and Lawrence Berkeley National Laboratory
    • UC Berkeley

  • J.D. Denlinger

    • Advanced Light Source, Lawrence Berkeley National Laboratory
    • Lawrence Berkeley Nat'l Lab

  • Katherine Benavides

    • Department of Chemistry and Biochemistry, The University of Texas at Dallas

  • Julia Chan

    • UT-Dallas
    • Department of Chemistry and Biochemistry, University of Texas at Dallas
    • University of Texas at Dallas
    • Department of Chemistry and Biochemistry, The University of Texas at Dallas