Pressure Control of Crystal Symmetry, Fermi Surface Reconstruction and Superconductivity in Weyl semimetal MoTe<sub>2</sub>

ORAL

Abstract

Layered transition metal chalcogenides are promising hosts of electronic Weyl nodes and topological superconductivity. MoTe2 is a striking example that harbors both non-centrosymmetric Td and centrosymmetric T' phases. In this talk we present neutron scattering and transport mreasuremens along with Density functional theory (DFT) calculations to suggest a path towards the realization and control of these topological states of the type-II Weyl semimetal and superconductor MoTe2 through the application of pressure [1]. DFT calculations reveal that the strength of the electron-phonon coupling is similar for both crystal structures. Finally, we show that there is a critical pressure characterized by unique coherent quantum oscillations, indicating that the change in topology between two phases give rise to a new topological interface state[2]. We present periodic and finite slab calculations of this new interface state which is in excellent agreement with the observed quantum oscillation frequencies.

[1] C. Heies et al, “Mechanical control of crystal symmetry and superconductivity in Weyl semimetal MoTe2”, Phys. Rev. Materials 2, 074202 (2018)
[2] I-Lin Liu et al, Quantum oscillations from networked topological interfaces in a Weyl
Semimetal, arxiv.org/1905.02277 (2019).

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Presenters

  • Taner Yildirim

    • National Institute of Standards and Technology

Authors

  • Taner Yildirim

    • National Institute of Standards and Technology

  • I-Lin Liu

    • Physics Department, University of Maryland
    • Department of Physics, University of Maryland, College Park
    • University of Maryland, College Park
    • NIST Center for Neutron Research

  • Colin Heikes

    • National Institute of Standards and Technology

  • Chris Eckberg

    • University of Maryland, College Park
    • Physics Department, University of Maryland

  • Tristin Metz

    • University of Maryland, College Park
    • Physics Department, University of Maryland
    • Center for Quantum Materials, University of Maryland

  • Sheng Ran

    • NIST Center for Neutron Research, National Institute of Standards and Technology
    • University of Maryland, College Park
    • National Institute of Standards and Technology
    • Physics Department, University of Maryland
    • University of Maryland
    • University of Maryland, College Park & NIST
    • Department of Physics, University of Maryland, College Park
    • NIST Center for Neutron Research

  • William Ratcliff

    • National Institute of Standards and Technology

  • Johnpierre Paglione

    • University of Maryland, College Park
    • Physics Department, University of Maryland
    • Maryland Quantum Materials Center, Department of Physics, University of Maryland College Park
    • Department of Physics, University of Maryland, College Park
    • University of Maryland, College Park & NIST
    • Univ of Maryland-Colege Park
    • Center for Quantum Materials, University of Maryland
    • Maryland Quantum Materials Center, Department of Physics, University of Maryland-College Park,College Park, Maryland 20742

  • Nicholas Butch

    • NIST 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
    • Center for Neutron Research, National Institute of Standards and Technology
    • NIST Center for Neutron Research
    • NIST center for neutron research
    • NIST
    • NIST Center for Neutron Research, National Institute of Standards and Technology,
    • University of Maryland, College Park & NIST
    • National Institute of Standards and Technology Center for Neutron Research