Magnetic and topological properties of Kagome metal YMn<sub>6</sub>Sn<sub>6</sub>

ORAL

Abstract

The Kagome lattice has historically been known for frustration-driven novel phenomena, such as spin-liquid phases. Recent experiments have indicated that 3D kagome magnets provide a natural platform to study the effect of the interplay between magnetism and electronic topology. For example, Weyl fermions and a non-collinear spin texture are observed in Mn3Sn, heavy Dirac bands are reported in frustrated ferromagnet Fe3Sn2, and flat bands and Dirac cones are realized in antiferromagnetic FeSn. Here we present our recent findings of the complex nature of the magnetism and topological features in the electronic structure of a ternary kagome magnet, YMn6Sn6. This compound orders with a commensurate antiferromagnetic helical structure below 340 K, which on cooling shows an incommensurate double helical structure. Both wave vectors are temperature dependent with the difference in q between the two helices gradually decreasing with decreasing temperature but remaining in the ground state. Electronic band structure calculations show the presence of a Dirac point near the Fermi energy, and a linear magnetoresistance is observed at low temperature when a magnetic field is applied along c-axis.

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Presenters

  • Nirmal Ghimire

    • Department of Physics and Astronomy, George Mason University
    • George Mason University
    • Argonne Natl Lab

Authors

  • Nirmal Ghimire

    • Department of Physics and Astronomy, George Mason University
    • George Mason University
    • Argonne Natl Lab

  • Lekhanath Poudel

    • NIST Center for Neutron Research
    • NIST Center for Neutron Research, National Institute of Standards and Technology
    • Department of Materials Science and Engineering, University of Maryland, College Park

  • Rebecca Dally

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

  • Nishchal Thapa Magar

    • Department of Physics and Astronomy, George Mason University

  • Nicholas Bishop

    • Department of Physics and Astronomy, George Mason University

  • Michael McGuire

    • Oak Ridge National Laboratory
    • Materials Science and Technology Division, Oak Ridge National Laboratory
    • Oak Ridge National Lab
    • Materials Science Division, Oak Ridge National Laboratory

  • J Samuel Jiang

    • Argonne National Laboratory
    • Materials Science Division, Argonne National Laboratory
    • Argonne Natl Lab

  • Igor Mazin

    • Naval Research Laboratory
    • Department of Physics and Astronomy, George Mason University
    • Naval Research Laboratory (currently at George Mason University)

  • John Mitchell

    • Argonne National Laboratory
    • Materials Science Division, Argonne National Laboratory
    • Argonne Natl Lab
    • Materials Science Division, Argonne National Lab
    • Material Science Division, Argonne National Lab

  • Jeffrey Lynn

    • 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 Standards and Technology
    • NIST Center for Neutron Research