Observation of anisotropic Dirac cones in the topological material Ti<sub>2</sub>Te<sub>2</sub>P

POSTER

Abstract

Anisotropic bulk Dirac (or Weyl) cones in three-dimensional systems have recently gained intense research interest as they are examples of materials with tilted Dirac (or Weyl) cones indicating the violation of Lorentz invariance. In contrast, the studies on anisotropic surface Dirac cones in topological materials which contribute to anisotropic carrier mobility have been limited. By employing angle-resolved photoemission spectroscopy and first-principles calculations, we reveal the anisotropic surface Dirac dispersion in a tetradymite material Ti2Te2P on the (001) plane of the Brillouin zone. We observe quasi-elliptical Fermi pockets at the M point of the Brillouin zone forming the anisotropic surface Dirac cones. Our calculations of the Z2 indices confirm that the system is topologically nontrivial with multiple topological phases in the same material. In addition, the observed nodal-line-like feature formed by bulk bands makes this system topologically rich.

*This work is supported by the Air Force Office of Scientific Research under Award No. FA9550-17-1-0415, the Air Force Office of Scientific Research MURI (Grant No. FA9550-20-1-0322), and the National Science Foundation (NSF) CAREER Award No. DMR-1847962.

Presenters

  • Iftakhar Bin Elius

    • University of Central Florida
    • University of Central FLorida

Authors

  • Iftakhar Bin Elius

    • University of Central Florida
    • University of Central FLorida

  • Gyanendra Dhakal

    • University of Central Florida

  • Firoza Kabir

    • University of Central Florida

  • Ashis Nandy

    • School of Physical Sciences, National Institute of Science Education and Research, Homi Bhabha National Institute, Jatni 752050, India
    • National Institute of Science Education and Research
    • School of Physical Sciences, National Institute of Science Education and Research, An OCC of Homi Bhabha National Institute, Jatni-752050, India

  • Alexandros Aperis

    • Uppsala University

  • Anup Pradhan Sakhya

    • University of Central Florida
    • Department of Physics, University of Central Florida, Orlando, Florida 32816, USA

  • Subhadip Pradhan

    • School of Physical Sciences, National Institute of Science Education and Research, of Homi Bhabha National Institute, Jatni 752050, India

  • Klauss M Dimitri

    • University of Central Florida

  • Christopher Sims

    • Department of Physics, University of Central Florida, Orlando, Florida 32816, USA

  • Sabin Regmi

    • University of Central Florida
    • University of Central Florida; Idaho National Laboratory

  • Md Mofazzel Hosen

    • Department of Physics, University of Central Florida, Orlando, Florida 32816, USA
    • Boston College

  • Yangyang Liu

    • University of Central Florida

  • Luis E Persaud

    • University of Central Florida

  • Dariusz Kaczorowski

    • Polish Academy of Sciences
    • Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Okolna 2, PL-50-420 Wroclaw, Poland
    • Institute of Low Temperature and Structure Research, Polish Academy of Sciences

  • Peter M Oppeneer

    • Uppsala University

  • Madhab Neupane

    • University of Central Florida