Observation of topological nodal-loop fermionic state in CaAs<sub>3</sub> family

ORAL

Abstract

Nontrivial states in topological semimetals are attracting intense interest driven by their numerous novel properties such as high bulk carrier mobility, Fermi arcs, chiral anomaly, large negative magnetoresistance, and high density of states. Here, using high-resolution angle-resolved photoemission spectroscopy (ARPES) along with first-principles calculations, we report the discovery of a topological nodal-loop (TNL) state in CaAs3 family. Our analysis reveals that surface projections of the bulk nodal-points are connected by surface states. Notably, the observed topological state in CaAs3 family are well separated from other bands in the vicinity of the Fermi level. CaAs3 family thus offers a unique materials realization of a prototype nodal-loop semimetal, and a platform for gaining a deeper understanding of the interplay between TNL and topological insulator physics in semimetals.

*This work is supported by the Air Force Office of Scientific Research under Award No. FA9550-17-1-0415 and the startup fund from UCF (M.N.).

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Presenters

  • Md Mofazzel Hosen

    • University of Central Florida
    • Physics, University of Central Florida, Orlando, Florida 32816, USA
    • Physics, University of Central Florida

Authors

  • Md Mofazzel Hosen

    • University of Central Florida
    • Physics, University of Central Florida, Orlando, Florida 32816, USA
    • Physics, University of Central Florida

  • Gyanendra Dhakal

    • University of Central Florida
    • Physics, University of Central Florida, Orlando, Florida 32816, USA
    • Physics, University of Central Florida

  • Baokai Wang

    • Northeastern University
    • Physics, Northeastern University, Boston, Massachusetts 02115, USA
    • Department of Physics, Northeastern University

  • Klauss Dimitri

    • University of Central Florida
    • Physics, University of Central Florida, Orlando, Florida 32816, USA
    • Physics, University of Central Florida

  • Firoza Kabir

    • University of Central Florida
    • Physics, University of Central Florida, Orlando, Florida 32816, USA
    • Physics, University of Central Florida

  • Christopher Sims

    • University of Central Florida
    • Physics, University of Central Florida, Orlando, Florida 32816, USA

  • Sabin Regmi

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

  • Yangyang Liu

    • University of Central Florida

  • Tomasz Durakiewicz

    • National Science Foundation
    • Los Alamos National Laboratory

  • Dariusz Kaczorowski

    • Polish Academy of Sciences
    • Institute of Low Temperature and Structure Research, Polish Academy of Sciences, 50-950 Wroclaw, Poland
    • Institute of Low Temperature and Structure Research, Polish Academy of Sciences
    • Polish Academy of Science

  • Arun Bansil

    • Northeastern University
    • Department of Physics, Northeastern University

  • Madhab Neupane

    • University of Central Florida
    • Physics, University of Central Florida, Orlando, Florida 32816, USA
    • Physics, University of Central Florida