Pressure Control of Crystal Symmetry, Fermi Surface Reconstruction and Superconductivity in Weyl semimetal MoTe2

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