APS Logo

Chern numbers and nodal points in topological semi metals.

Invited

Abstract

Nonmagnetic topological materials have dominated the landscape of topological physics for the past two decades. These breakthroughs in non-magnetic materials have not yet been matched by similar advances in magnetic compounds. Using magnetic band theory and topological indices obtained from Magnetic Topological Quantum Chemistry (MTQC), I will present a systematic way of identifying magnetic topological materials. I will then, focus on high order magnetic semimetals, and provide a topological classification of different fermions in these phases. Finally I will present new experimental realizations in materials. In particular I will focus on the pyrite compound CoS2, using complementary bulk- and surface-sensitive angle-resolved photoelectron spectroscopy and ab-initio calculations we discovered Weyl-cones at the Fermi-level and we directly observed the topological Fermi-arc surface states that link the Weyl-nodes, which will influence the performance of CoS2 as a spin-injector by modifying its spin-polarization at interfaces.
[1] Yuanfeng Xu, Luis Elcoro, Zhi-Da Song, Benjamin J Wieder, MG Vergniory, et al. Nature 586 (7831), 702-707 (2020)
[2] Jennifer Cano, Barry Bradlyn, MG Vergniory, APL Materials 7 (10), 101125 (2019)
[4] Niels Schröter, Iñigo Robredo, et al. arXiv preprint arXiv:2006.01557 , Accepted in Science Advances (2020)

–

Presenters

  • Maia Garcia Vergniory

    Donostia International Physics Center, Donostia International Physics Center-DIPC, Donostia International Physics Center, Spain, Donastia nternational Physics Center, San Sebastian, Spain

Authors

  • Maia Garcia Vergniory

    Donostia International Physics Center, Donostia International Physics Center-DIPC, Donostia International Physics Center, Spain, Donastia nternational Physics Center, San Sebastian, Spain

  • Yuanfeng Xu

    Max Planck Institute of Microstructure Physics, Max Planck Institute, Halle, Germany, Physics, Max Planck Institute of Microstructure, Max Planck Inst Microstructure

  • Benjamin Wieder

    Princeto University, Princeton, USA

  • Iigo Robredo

    Donostia International Physics Center, Donostia International Physics Center, Spain

  • Luis Elcoro

    Department of Condensed Matter Physics, University of the Basque Country, University of the Basque Country UPV/EHU, University of the Basque Country, University of the Basque Country, Spain

  • Nicolas Regnault

    Department of Physics, Princeton University, Princeton University, Princeton University, CNRS, ENS Paris, Princeto University, Princeton, USA

  • Niels Schroeter

    Paul Scherrer Institute, Switzerland

  • Jennifer Cano

    Stony Brook University, Stony Brook University, USA, Physics and Astronomy, Stony Brook University, Flatiron Institute; Stony Brook Univ., Department of Physics, Stonybrook University, Department of Physics and Astronomy, Stony Brook University, State Univ of NY - Stony Brook

  • Barry Bradlyn

    University of Illinois at Urbana-Champaign, Department of Physics, University of Illinois, Department of Physics, University of Illinois at Urbana-Champaign, University of Illinois Urbana-Champaign, USA, Department of Physics and Institute for Condensed Matter Theory, University of Illinois at Urbana-Champaigm

  • Leslie M Schoop

    Princeton University, Princeto University, Princeton, USA, Department of Chemistry, Princeton University

  • Claudia Felser

    Max Planck Institute for Chemical Physics of Solids, Max Planck Institute for the Chemical Physics of Solids, Solid State Chemistry, Max Planck Institute for Chemical Physics of Solids, Max Planck Institute, Dresden, Germany, Max Planck, Dresden, Max Planck Institute for Chemical Physics of Solids, 01187 Dresden, Max Planck Institute for Chemical Physics of Solids,

  • Andrei B Bernevig

    Department of Physics, Princeton University, Princeton University, Princeto University, Princeton, USA, Physics, Princeton University