Observation of Dirac-like state in Antiferromagnetic Semimetal EuMg<sub>2</sub>Bi<sub>2</sub>

ORAL

Abstract

Topological Dirac semimetals, systems containing low energy relativistic Dirac quasiparticle excitations, have received ample attention in condensed matter physics. Early work on Dirac semimetals focused on nonmagnetic systems with the presence of time reversal symmetry. Recent interest has turned toward the study of magnetic Dirac materials. Here, we have studied the transport and the electronic structure of Eu-ternary pnictide EuMg2Bi2 by utilizing high-resolution angle-resolved photoemission spectroscopy (ARPES) which is supplemented by first-principles calculations. We have performed electrical resistivity, magnetization, and specific heat capacity measurements of EuMg2Bi2 and confirm the existence of antiferromagnetic ordering below the temperature of 6.7 K. Our ARPES measurement reveals the electronic structure of this system is dominated by linearly dispersive hole-like bands near the Fermi level. First principles calculations show excellent agreement with these observations. Furthermore, our results also suggest the presence of a single Dirac point above the experimental Fermi level. These findings give an opportunity to study the interplay between topology and magnetism.

*M.N. is supported by the Air Force Office of Scientific Research for MURI Grant No. FA9550-20-1-0322 and the National Science Foundation under the CAREER award DMR-1847962.

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Presenters

  • Mazharul Islam Mondal

    • University of Central Florida

Authors

  • Mazharul Islam Mondal

    • University of Central Florida

  • Milo Sprague

    • University of Central Florida
    • Department of Physics, University of Central Florida

  • Anup Pradhan Sakhya

    • University of Central Florida
    • Department of Physics, University of Central Florida

  • Sabin Regmi

    • Idaho National Laboratory
    • University of Central Florida
    • Department of Physics, University of Central Florida; Center for Quantum Actinide Science and Technology, Idaho National Laboratory
    • Department of Physics, University of Central Florida; Idaho National Laboratory

  • Iftakhar Bin Elius

    • University of central Florida
    • University of Central Florida
    • Department of Physics, University of Central Florida

  • Nathan A Valadez

    • University of Central Florida
    • Department of Physics, University of Central Florida

  • Peter M Oppeneer

    • Uppsala University

  • Andrzej Ptok

    • Institute of Nuclear Physics, Polish Academy of Sciences

  • Dariusz Kaczorowski

    • Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Ok´olna 2, 50-422 Wroc law, Poland
    • Polish Academy of Sciences
    • Institute of Low Temperature and Structure Research, Polish Academy of Sciences

  • Madhab Neupane

    • University of Central Florida
    • Department of Physics, University of Central Florida