Electronic topology-driven helicoid arc van Hove singularities in tunable chiral fermion conductors

ORAL

Abstract

The classification scheme of electronic phases uses two prominent paradigms: correlations and topology. Electron correlations give rise to superconductivity and charge density waves, while the quantum geometric Berry phase gives rise to electronic topology. The intersection of these two paradigms has initiated an effort to discover electronic instabilities at or near the Fermi level of topological materials. Here, we identify the electronic topology of chiral fermions as the driving mechanism for creating van Hove singularities that host electronic instabilities in the surface band structure. We observe that the chiral fermion conductors RhSi and CoSi possess two types of helicoid arc van Hove singularities that we call type-I and type-II. In RhSi, the type-I variety drives a switching of the connectivity of the helicoid arcs at different energies. In CoSi, we measure a type-II intra-helicoid arc van Hove singularity near the Fermi level. Chemical engineering methods are able to tune the energy of these singularities. Finally, electronic susceptibility calculations allow us to visualize the dominant Fermi surface nesting vectors of the helicoid arc singularities, consistent with recent observations of surface charge density wave ordering in CoSi. This suggests a connection between helicoid arc singularities and surface charge density waves.

*Princeton-led measurements were supported by the United States Department of Energy (US DOE) under the Basic Energy Sciences program (grant number DOE/BES DE-FG-02-05ER46200). This research used resources of the Advanced Light Source, which is a DOE Office of Science User Facility under contract No. DE-AC02-05CH11231. We acknowledge the Paul Scherrer Institut for provision of synchrotron radiation beamtime at the ADRESS beamline of the Swiss Light Source. We acknowledge the support of the National Research Foundation, Singapore under its NRF Fellowship Award No. NRF-NRFF13-2021-0010 and the Nanyang Assistant Professorship grant from Nanyang Technological University. We acknowledge department of atomic energy (DAE), Govt. of India for the funding support via Young scientist's research award (YSRA) with grant no. 58/20/03/2021-BRNS/37084. T.A.C. acknowledges the National Science Foundation Graduate Research Fellowship Program with Grant No. DGE-1656466.

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Publication: D. S. Sanchez, T. A. Cochran, ...., M. Z. Hasan. Electronic topology-driven helicoid arc van Hove singularities in tunable chiral fermion conductors. (Accepted)

T. A. Cochran, ..., M. Z. Hasan. Visualizing higher-fold topology in chiral crystals. (Submitted)

G. Chang, ..., M. Z. Hasan. Topological quantum properties of chiral crystals. Nat. Mater. 17, 978 (2018).

Presenters

  • Tyler A Cochran

    • Princeton University

Authors

  • Tyler A Cochran

    • Princeton University

  • Daniel S Sanchez

    • Princeton University

  • Ilya Belopolski

    • RIKEN
    • RIKEN CEMS

  • Zi-Jia Cheng

    • Princeton University

  • Xian Yang

    • Princeton University

  • Xitong Xu

    • Peking Univ

  • Kaustuv Manna

    • Max Planck Institute for Chemical Physics of Solids

  • Chandra Shekhar

    • Max Planck Institute for Chemical Physics of Solids

  • Jiaxin Yin

    • Princeton University

  • Horst Borrmann

    • Max Planck Intitute for the Chemical Physics of Solids
    • Max Planck Institute for Chemical Physics of Solids

  • Jonathan D Denlinger

    • Lawrence Berkeley National Laboratory
    • Lawrence Berkeley National Laboratory, Berkeley, California

  • Vladimir N Strocov

    • Swiss Light Source, Paul Scherrer Institut
    • Swiss Light Source, Paul Scherrer Insitute
    • Swiss Light Source
    • Paul Scherrer Institut

  • Weiwei Xie

    • Michigan State University
    • Department of Chemistry, Michigan State University

  • Claudia Felser

    • Max Planck Institute for Chemical Physic
    • Max Planck Institute for Chemical Physics of Solids

  • Shuang Jia

    • Peking Univ

  • Guoqing Chang

    • Nanyang Technological University
    • Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore
    • Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 637371 Singapore

  • M. Zahid M Hasan

    • Princeton University