Universal Topological Electronic Properties of Nonmagnetic Chiral Crystals

ORAL

Abstract

Chiral crystals are materials whose lattice structure has a well-defined handedness due to the lack of inversion, mirror, or other roto-inversion symmetries. Their structural chirality has been found to allow a wide range of phenomena, including skyrmions in chiral magnets, unconventional pairing in chiral superconductors, nonlocal transport and unique magnetoelectric effects in chiral metals. We show a universal topological electronic property of all nonmagnetic chiral crystals with spin-orbit coupling. In these materials, the combination of structural chirality and time-reversal symmetry is sufficient to guarantee the presence of two-fold-degenerate chiral fermions at the time-reversal invariant momenta, Kramers-Weyl. We further show that Kramers-Weyl fermions enable a number of unique topological phenomena, including a quantized photogalvanic current, the chiral and gyrotropic magnetic effects and electron spin-momentum locking. Considering the abundance of chiral crystals, our findings are widely applicable. The symmetry-guaranteed presence of these fermions in all chiral crystals provides a new and reliable means of engineering and controlling the unconventional optical, transport, and superconducting properties of chiral materials[1].
1.G. Chang et al., arXiv: 1611.07925

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Presenters

  • Guoqing Chang

    • National University of Singapore
    • Institute of Physics, Academica Sinica
    • Institute of Physics, Academia Sinica
    • Princeton Univ
    • National U. of Singapore

Authors

  • Guoqing Chang

    • National University of Singapore
    • Institute of Physics, Academica Sinica
    • Institute of Physics, Academia Sinica
    • Princeton Univ
    • National U. of Singapore

  • Benjamin Wieder

    • Princeton Univ
    • Department of Physics, Princeton University

  • Frank Schindler

    • University of Zurich
    • Department of Physics, University of Zurich

  • Daniel Sanchez

    • Princeton Univ
    • Princeton University
    • Princeton U.

  • Ilya Belopolski

    • Princeton Univ
    • Princeton University
    • Princeton U.

  • Shin-Ming Huang

    • National Sun Yat-sen University
    • Department of Physics, National Sun Yat-sen University
    • National Sun Yat-Sen University
    • National Sun Yat-Sen U.
    • Department of Physics, National Sun Yat-Sen University
    • Physic, Natl Sun Yat Sen Univ
    • Physics, Natl Sun Yat Sen Univ

  • Bahadur Singh

    • National University of Singapore

  • Di Wu

    • National University of Singapore

  • Tay-Rong Chang

    • Physics, National Cheng Kung University
    • National Cheng Kung University
    • Department of Physics, National Tsing Hua University
    • Natl Cheng Kung U.

  • Titus Neupert

    • University of Zurich
    • Department of Physics, University of Zurich
    • U. of Zurich

  • Suyang Xu

    • MIT
    • Department of Physics, Massachusetts Institute of Technology
    • Massachusetts Institute of Technology
    • Princeton University
    • Princeton U.
    • Massachusetts Inst of Tech-MIT

  • Hsin Lin

    • Academia Sinica
    • National University of Singapore
    • Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore
    • Institute of Physics, Academica Sinica
    • Institute of Physics, Academia Sinica
    • National U. of Singapore
    • Natl Univ of Singapore
    • National University of Signapore

  • Zahid Hasan

    • Princeton Univ
    • Princeton University
    • Princeton U.