Circular dichroism in the angle-resolved photoemission spectra of the charge density wave Weyl semimetal (TaSe<sub>4</sub>)<sub>2</sub>I

ORAL

Abstract

(TaSe4)2I is a Weyl semimetal candidate that undergoes a charge density wave (CDW) transition on its quasi-one-dimensional lattice. This makes it an ideal system to study the interplay between topological effects and strong correlations. In particular, the onset of CDW order links two Weyl nodes near the Fermi surface to open up a gap leading to axion electrodynamics. In this work, we explore the band structure of (TaSe4)2I in the proximity of Weyl nodes with high momentum resolution laser-based angle-resolved photoemission (ARPES). Our results show strong circular dichroism in the measured ARPES spectra both above and below the CDW transition temperature (~260 K). We will discuss the implications of our results based on the predicted spin/orbital texture and effects of CDW on the electronic band structure of (TaSe4)2I near the Weyl nodes.

*This work is supported by the QSQM, an Energy Frontier Research Center funded by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), under Award # DE-SC0021238.

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Presenters

  • So Yeun Kim

    • Department of Physics, University of Illinois at Urbana-Champaign

Authors

  • So Yeun Kim

    • Department of Physics, University of Illinois at Urbana-Champaign

  • Nina Bielinski

    • University of Illinois at Urbana-Champaign
    • Department of Physics, University of Illinois at Urbana-Champaign

  • Chengxi Zhao

    • Materials Research Laboratory, University of Illinois at Urbana-Champaign

  • Robert McKay

    • Department of Physics, University of Illinois at Urbana-Champaign
    • University of Illinois at Urbana-Champaign

  • Barry Bradlyn

    • University of Illinois at Urbana-Champaign
    • Department of Physics, University of Illinois
    • Department of Physics, University of Illinois at Urbana-Champaign
    • University of Illinois Urbana-Champaign, USA
    • Department of Physics and Institute for Condensed Matter Theory, University of Illinois at Urbana-Champaigm

  • Daniel Shoemaker

    • University of Illinois at Urbana-Champaign
    • Materials Research Laboratory, University of Illinois at Urbana-Champaign

  • Fahad Mahmood

    • University of Illinois at Urbana-Champaign
    • Department of Physics, University of Illinois at Urbana-Champaign
    • Material Science and Engineering, University of Illinois at Urbana-Champaign
    • Physics, University of Illinois at Urbana-Champaign