Correlating the crystal structure and electronic ground state of type-II Weyl semimetal MoTe$_2$: structural measurements

ORAL

Abstract

The reported pressure dependent superconductivity of the type-II Weyl semimetal MoTe$_2$ has led to speculation about the possibility of a topologically non-trivial superconducting state in this material. A key question about the topology of this superconducting state is the evolution of the crystal structure of MoTe$_2$ at pressures and temperatures relevant for superconductivity, as the non-centrosymmetric T$_d$ orthorhombic phase is needed for the Weyl state. Semimetallic MoTe$_2$ has two metastable polymorphs, with a first order structural transition between the centrosymmetric monoclinic 1T’ and the orthorhombic T$_d$ structure near 270 K. This structural transition has a demonstrated pressure dependence, with a suppression of the T$_d$ phase at increased pressures. We have grown single crystals of MoTe$_2$, and using a combination of elastic neutron scattering, magnetotransport, and spectroscopic techniques we have investigated the nature of this transition. We report pressure and temperature dependent neutron scattering measurements which elucidate the nature of this phase transition at temperature and pressures relevant for the previously reported superconductivity.

*NIST Center for Neutron Research

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Presenters

  • Colin Heikes

    • Center for Neutron Research, NIST -Natl Inst of Stds & Tech

Authors

  • Colin Heikes

    • Center for Neutron Research, NIST -Natl Inst of Stds & Tech

  • I-Lin Liu

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

  • Linda Hung

    • NIST Center for Neutron Research, Natl Inst of Stds & Tech
    • Center for Neutron Research, NIST -Natl Inst of Stds & Tech

  • Tristin Metz

    • Univ of Maryland-College Park
    • Department of Physics, University of Maryland
    • Center for Nanophysics and Advanced Materials, University of Maryland

  • Chris Eckberg

    • CNAM, Department of Physics, University of Maryland
    • Univ of Maryland-College Park
    • Department of Physics, University of Maryland

  • Yan Wu

    • Neutron Sciences Directorate, Oak Ridge National Laboratory
    • Oak Ridge National Lab
    • Physics, Louisiana State Univ

  • Huibo Cao

    • Neutron Scattering Division, Oak Ridge National Laboratory
    • Oak Ridge National Laboratory
    • Quantum Condensed Matter Division, Oak Ridge National Laboratory
    • Neutron Sciences Directorate, Oak Ridge National Laboratory
    • Neutron Scattering Division, Oak Ridge National Lab
    • Oak Ridge National Lab
    • Oak Ridge Natl Lab
    • Quantum Condensed Matter Division , Oak Ridge National Laboratory

  • Johnpierre Paglione

    • Center for Nanophysics and Advanced Materials , University of Maryland
    • CNAM, Department of Physics, University of Maryland
    • Univ of Maryland-College Park
    • Department of Physics, University of Maryland
    • CNAM, Department of Physics, Univ of Maryland-College Park
    • Univ of Maryland - College Park
    • College Park, MD 20742-4111, Univ of Maryland-College Park
    • Center for Nanophysics and Advanced Materials, Department of Physics, University of Maryland
    • Center for Nanophysics and Advanced Materials, University of Maryland
    • University of Maryland, College Park
    • University of Maryland

  • Taner Yildirim

    • NIST Center for Neutron Research, Natl Inst of Stds & Tech
    • NIST- Natl Inst of Stds & Tech
    • Center for Neutron Research, NIST -Natl Inst of Stds & Tech

  • Nicholas Butch

    • NIST Center for Neutron Research, National Institute of Standards and Technology
    • NIST Center for Neutron Research
    • NIST- Natl Inst of Stds & Tech
    • Center for Neutron Research, NIST -Natl Inst of Stds & Tech
    • NIST -Natl Inst of Stds & Tech
    • NIST center for neutron research
    • NIST

  • William Ratcliff

    • NIST
    • NIST- Natl Inst of Stds & Tech
    • Center for Neutron Research, NIST -Natl Inst of Stds & Tech
    • NIST -Natl Inst of Stds & Tech
    • NCNR, NIST -Natl Inst of Stds & Tech