Pnictide square net materials with reduced symmetry, the rare earth diantimonides: electronic structure and topology

ORAL

Abstract

With the discovery of Dirac fermions, much research effort has been put into finding the structural elements that can generate Dirac-like degeneracies in the electronic band structures [1]. It was discovered that some layered materials can host planar square nets of group IV-V elements within their lattice. Analogously to graphene, these square nets possess a 2-atom basis and feature wide Dirac bands. Most of the known layered compounds that retain the electronic properties of the net, such as (Sr,Ca)MnBi2 and ZrSiS, crystallize in a tetragonal structure, and exhibit a Dirac semimetal or nodal line phase that can host a rich plethora of electronic and magnetic quantum properties [2]. In this talk we will show a new variety of square net semimetals whose structure breaks the 4-fold symmetry, the rare earth di-antimonides. These materials crystallize in the orthorhombic group Cmca reducing the overall symmetry of the system. We employed ARPES and DFT calculations on the series precursor, LaSb2, to study its electronic structure. We will discuss the effect that the symmetry reduction has on the electronic properties, on the Dirac states, as well as its interplay with spin-orbit coupling.
[1] B. Bradlyn et al., Nature 547, 298 (2017)
[2] S. Klemenz et al., Arxiv:1808.06619v1 (2018)

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Presenters

  • Matteo Michiardi

    University of British Colombia, QMI, University of British Columbia, Physics and Astronomy, University of British Columbia, Quantum Matter Institute, University of British Columbia, Department of Physics & Astronomy, University of British Columbia

Authors

  • Matteo Michiardi

    University of British Colombia, QMI, University of British Columbia, Physics and Astronomy, University of British Columbia, Quantum Matter Institute, University of British Columbia, Department of Physics & Astronomy, University of British Columbia

  • Fabian Arnold

    Physics and Astronomy, Aarhus University

  • Elia Razzoli

    University of British Colombia, QMI, University of British Columbia, Physics and Astronomy, University of British Columbia, Quantum Matter Institute, University of British Columbia, Department of Physics & Astronomy, University of British Columbia

  • Karl F. Fisher

    Department of chemistry, Aarhus University

  • Vaitheeswaran Ganapathy

    Andvanced Center for Research in high energy materials, Hyderabad University

  • Giorgio Levy

    University of British Colombia, QMI, University of British Columbia, Physics and Astronomy, University of British Columbia, Quantum Matter Institute, University of British Columbia, Department of Physics & Astronomy, University of British Columbia

  • Fabio Boschini

    University of British Colombia, QMI, University of British Columbia, Physics and Astronomy, University of British Columbia, Quantum Matter Institute, University of British Columbia, Department of Physics & Astronomy, University of British Columbia

  • Ilya Elfimov

    Quantum Matter Institute, University of British Columbia, Stewart Blusson Quantum Matter Institute

  • Bo B Iversen

    Department of chemistry, Aarhus University

  • Philip Hofmann

    Physics and Astronomy, Aarhus University

  • Andrea Damascelli

    University of British Columbia, University of British Colombia, QMI, University of British Columbia, Physics and Astronomy, University of British Columbia, Stuart Blussom Quantum Matter Institute, University of British Columbia, Quantum Matter Institute, University of British Columbia, Department of Physics & Astronomy, University of British Columbia