Ferromagnetic Weyl semimetals and their electromagnetic response in RAlX materials class (R= Ce or Pr and X = Si or Ge)

ORAL

Abstract

Ferromagnetic Weyl semimetals (FMWSMs) are exotic topological materials in which nontrivial band topology and magnetism drive novel electromagnetic responses such as the anomalous Hall effect (AHE). Currently available FMWSMs are limited to materials that preserve the inversion symmetry and generate the Weyl nodes by breaking the time-reversal symmetry (TRS). Here we present RAlX materials (R= Ce, Pr; X = Si, Ge) as new FMWSMs where the Weyl nodes are stabilized by breaking the inversion symmetry and their separation is controlled by breaking TRS. They show an unconventional AHE that can be tuned continuously by controlling the dispersion of the Weyl nodes. Based on our systematic first-principles calculations and transport measurements, we show that PrAlGe1-xSix (x = 0-1) is a type II FMWSM with an AHE that shows a transition from an intrinsic mechanism driven by the Berry curvature to an extrinsic scattering mechanism [1]. In contrast, CeAlSi is a noncollinear FMWSM with type I Weyl nodes [2]. It shows an AHE that appears (disappear) as the Fermi level is tuned to lie close to (away from) the Weyl nodes. Our study uncovers RAlX as a new, tunable FMWSM family hosting unconventional AHE.

1. H.-Y. Yang et al., APL Mater. 8, 011111 (2020).
2. H.-Y. Yang et al., arXiv: 2006.07943v2.

–

Presenters

  • Cheng-Yi Huang

    • Department of Physics, Northeastern University
    • Physics, Northeastern University
    • Physics, California State University, Northridge

Authors

  • Cheng-Yi Huang

    • Department of Physics, Northeastern University
    • Physics, Northeastern University
    • Physics, California State University, Northridge

  • Bahadur Singh

    • Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research
    • Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research
    • Department of Condensed Matter Physics and Material Science, Tata Institute of Fundamental Research
    • Tata Institute of Fundamental Research
    • Tata Institute for Fundamental Research
    • DCMPMS, Tata Institute of Fundamental Research, India
    • Condensed Matter Physics and Material Science, Tata Institute of Fundamental Research
    • Department of Condensed Matter Physics & Materials Science, Tata Institute of Fundamental Research

  • Hung-Yu Yang

    • Department of Physics, Boston College
    • Boston College
    • Department of Physics, Boston College, Chestnut Hill, MA 02467, USA

  • Baozhu Lu

    • Department of Physics and Temple Materials Institute, Temple University
    • Temple University

  • Faranak Bahrami

    • Department of Physics, Boston College
    • Boston College

  • Jonathan Gaudet

    • Department of Physics and Astronomy and Institute for Quantum Matter, The Johns Hopkins University
    • Johns Hopkins University
    • Department of Physics and Astronomy and Institute for Quantum Matter, Johns Hopkins University, Baltimore, Maryland 21218, USA

  • Bochao Xu

    • Department of Physics, University of Connecticut
    • University of Connecticut
    • Physics Department, University of Connecticut

  • Jacob D Franklin

    • Department of Physics, University of Connecticut
    • Physics Department, University of Connecticut
    • University of Connecticut

  • Ilya Sochnikov

    • Institute of Material Science, University of Connecticut
    • Department of Physics, University of Connecticut

  • David E Graf

    • National High Magnetic Field Laboratory
    • Florida State University
    • National High Magnetic Field Lab, Florida State University
    • National High Magnetic Field Laboratory, Tallahassee and Florida State University
    • National High Magnetic Field Laboratory, Florida State University
    • National High Magnetic Field Laboratory (FSU)
    • Department of Physics, Florida State University
    • National High Magnetic Field Laboratory and Department of Physics, Florida State University
    • National High Magnetic Field Lab
    • National High Magnetic Field Laboratory, Tallahassee, FL
    • CMS, National High Magnetic Laboratory

  • Guangyong Xu

    • NIST
    • NIST Center for Neutron Research, National Institute of Standards and Technology
    • National Institute of Standard and Technology
    • Center for Neutron Research, National Institute of Standards and Technology
    • National Institute of Standards and Technology
    • Center of Neutron Research, National Institute of Standards and Technology, NIST
    • NIST Center for Neutron Research, NIST

  • Yang Zhao

    • NIST Center for Neutron Research,, National Institute of Standards and Technology
    • NIST Center for Neutron Research, National Institute of Standards and Technology
    • National Institute of Standard and Technology
    • Center for Neutron Research, National Institute of Standards and Technology
    • National Institute of Standards and Technology

  • Christina Hoffmann

    • Neutron Scattering Division, Oak Ridge National Laboratory
    • Oak Ridge National Laboratory,

  • Collin Leslie Broholm

    • Johns Hopkins University
    • Department of Physics and Astronomy and Institute for Quantum Matter, The Johns Hopkins University
    • Department of Physics and Astronomy and Institute for Quantum Matter, Johns Hopkins University, Baltimore, Maryland 21218, USA
    • Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University
    • Physics, The Johns Hopkins University

  • Wei-Chi Chiu

    • Department of Physics, Northeastern University

  • Shin-Ming Huang

    • Department of Physics, National Sun Yat-sen University
    • National Sun Yat-Sen University

  • Baokai Wang

    • Department of Physics, Northeastern University
    • Northeastern University
    • Department of Physics, Northeastern University, USA

  • Hsin Lin

    • Institute of Physics, Academia Sinica
    • Academia Sinica
    • Institute of Physics, Academia Sinica, Taipei
    • Institute of Physics, Academia Sinica, Taiwan
    • Physics, Academia Sinica

  • Darius Torchinsky

    • Department of Physics and Temple Materials Institute, Temple University
    • Temple University

  • Arun Bansil

    • Department of Physics, Northeastern University
    • Northeastern University
    • NU
    • Department of Physics, Northeastern University, USA

  • Fazel Tafti

    • Boston College
    • Department of Physics, Boston College
    • Department of Physics, Boston College, Chestnut Hill, MA 02467, USA