Quasi-one-dimensional first- and second-order topological insulators: Bi<sub>4</sub>X<sub>4</sub> (X = Br, I)

ORAL

Abstract

Recently, quasi-one-dimensional materials Bi4X4 (X = Br, I) in both α and β crystalline phases have been proposed as a promising platform for the realization of various topological insulator (TI) phases [e.g., PRL 116, 066801 (2016)]. This list includes the strong TI, the weak TI, and the second-order TI with helical hinge states. We perform first-principles calculations and construct an effective model for Bi4X4. These results allow us to derive all the aforementioned TI phases and guide future experimental studies.

*This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. 2018R1A2B6007837), Creative-Pioneering Researchers Program through Seoul National University (C.Y and H.M), the Global Ph.D Fellowship Program through NRF of Korea funded by Korean Government under Grant No. 2016H1A2A1907780 (C.Y.), and the Army Research Office and was accomplished under Grant Number W911NF-18-1-0416. (F.Z.)

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Presenters

  • Chiho Yoon

    • Department of Physics and Astronomy, Seoul National University

Authors

  • Chiho Yoon

    • Department of Physics and Astronomy, Seoul National University

  • Cheng-Cheng Liu

    • Beijing Key Laboratory of Nanophotonics and Ultrane Optoelectronic Systems, School of Physics, Beijing Institute of Technology
    • School of Physics, Beijing Institute of Technology, Beijing, China
    • School of Physics, Beijing Institute of Technology

  • Hongki Min

    • Department of Physics and Astronomy, Seoul National University
    • Physics and Astronomy, Seoul National University
    • Department of Physics and Astronomy, SNU

  • Fan Zhang

    • Department of Physics, The University of Texas at Dallas
    • University of Texas at Dallas
    • Department of Physics, University of Texas at Dallas