Engineering Weyl phases and nonlinear Hall effects in T<sub>d</sub>-MoTe<sub>2</sub>

ORAL

Abstract

MoTe2 has recently attracted much attention due to the observation of pressure-induced superconductivity, exotic topological phase transitions, and nonlinear quantum effects. However, there is debate on the intriguing structural phase transitions among various observed phases of MoTe2, and their connection to the underlying topological electronic properties. In this work, by means of density-functional theory (DFT+U) calculations, we describe the structural phase transition between the polar Td and nonpolar 1T' phases of MoTe2 in reference to a hypothetical high-symmetry structure T0 that exhibits higher-order topological features. We obtain a total of 12 Weyl points, which can be created/annihilated, dynamically manipulated, and switched by tuning a zone-center polar phonon mode in the Td phase. We also report on the existence of a tunable nonlinear Hall effect in Td-MoTe2, and predict an emergent nonlinear surface current under the application of an external electric field. The potential technological applications of the tunable Weyl phase and nonlinear Hall effect will be discussed.

*Support from NSF DMREF Grant No. DMR-1629059, and ONR Grants N00014-16-1-2951 and N00014-17-1-2449 is acknowledged.

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Presenters

  • Sobhit Singh

    • Department of Physics and Astronomy, Rutgers University, New Brunswick, NJ, USA
    • Physics and Astronomy, Rutgers University

Authors

  • Sobhit Singh

    • Department of Physics and Astronomy, Rutgers University, New Brunswick, NJ, USA
    • Physics and Astronomy, Rutgers University

  • Jinwoong Kim

    • Department of Physics and Astronomy, Rutgers University, New Brunswick, NJ, USA
    • Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
    • Rutgers University, New Brunswick

  • Karin M Rabe

    • Department of Physics and Astronomy, Rutgers University, New Brunswick, NJ, USA
    • Rutgers University, New Brunswick
    • Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
    • Dept. of Physics and Astronomy, Rutgers University, New Brunswick
    • Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, United States
    • Department of Physics and Astronomy, Rutgers University, New Brunswick

  • David Vanderbilt

    • Department of Physics and Astronomy, Piscataway, NJ 08854, Rutgers University
    • Department of Physics and Astronomy, Rutgers University, New Brunswick, NJ, USA
    • Department of Physics & Astronomy, Rutgers University
    • Physics and Astronomy, Rutgers University
    • Department of Physics and Astronomy, Rutgers University
    • Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
    • Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, United States
    • Rutgers University
    • Physics, Rutgers University
    • Department of Physics and Astronomy, Rutgers University, New Brunswick
    • Rutgers University, New Brunswick