Topological tunability from even-odd order parameter mixing of monolayer 1T-TiSe<sub>2</sub> charge density wave

ORAL

Abstract

Monolayer 1T-TiSe2 has been found to have charge density wave (CDW) experimentally. The primary CDW order parameter takes the M1- symmetry having odd parity and will change parity of electronic states of the system. Due to the coexistence of three q vectors from the primary order parameter, a secondary order parameter of even parity is induced inevitably. The mixture of the two opposite-parity order parameters will break inversion symmetry, which fails connection between symmetry and topology. Here we propose a method to decouple the parity-odd and parity- even CDW gaps, so that we can perform continuously the inversion-asymmetric CDW state into an inversion-symmetric one. In this way it helps to understand topological phase transitions in inversion asymmetric systems from the inversion-symmetry point of view.

*The project is supported by the Ministry of Science and Technology (MoST) in Taiwan under grant No. 105-2112-M- 110-014-MY3 and also by the NCTS of Taiwan.

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Presenters

  • Ming-Chien Hsu

    • Physics, National Sun Yat-sen University
    • Department of Physics, National Sun Yat-sen University

Authors

  • Ming-Chien Hsu

    • Physics, National Sun Yat-sen University
    • Department of Physics, National Sun Yat-sen University

  • Shin-Ming Huang

    • Physics, National Sun Yat-sen University
    • National University of Singapore
    • Department of Physics, National Sun Yat-sen University

  • Bahadur Singh

    • SZU-NUS Collaborative Center and International Collaborative Laboratory of 2D Materials for Optoelectronic Science & Technology, Engineering Technology Research Center for 2D
    • Department of Physics, Northeastern University, Boston, Massachusetts 02115, USA /SZU-NUS Collaborative Center and International Collaborative Laboratory of 2D Materials for
    • Department of Physics, National University of Singapore
    • SZU-NUS Collaborative Center and International Collaborative Laboratory of 2D Materials for Optoelectronic Science \& Technology, Engineering Technology Research Center for 2
    • Department of Physics, Northeastern University
    • Shenzhen University, Shenzhen, China
    • College of Optoelectronic Engineering, Shenzhen University

  • Chuang-Han Hsu

    • Department of Physics, National University of Singapore

  • Suyang Xu

    • Department of Physics, Massachusetts Institute of Technology
    • Massachusetts Institute of Technology
    • MIT
    • Physics, MIT
    • Department of Physics, Massachusetts Institute of Technology, Cambridge

  • Hsin Lin

    • Academia Sinica
    • Institute of Physics, Academia Sinica
    • Physics, Academia Sinica, Taipei 11529, Taiwan
    • Institute of Physics, Academia Sinica, Taipei 11529, Taiwan
    • Physics, Academia Sinica
    • Department of Physics, National University of Singapore
    • National University of Singapore
    • Academia Sinica, Taipei, Taiwan

  • Chenliang Su

    • SZU-NUS Collaborative Center and International Collaborative Laboratory of 2D Materials for Optoelectronic Science & Technology, Engineering Technology Research Center for 2D
    • SZU-NUS Collaborative Center and International Collaborative Laboratory of 2D Materials for Optoelectronic Science \& Technology, Engineering Technology Research Center for 2
    • Shenzhen University, Shenzhen, China
    • SZU-NUS Collaborative Center and International Collaborative, Laboratory of 2D Materials for Optoelectronic Science & Technology, Engineering Technology Research Center for 2

  • Arun Bansil

    • Department of Physics, Northeastern University
    • Northeastern
    • Physics, Northeastern University, Boston, Massachusetts 02115, USA
    • Northeastern University
    • Northeastern University, Boston (MA), USA
    • Physics, Northeastern U.
    • Department of Physics, Northwestern University
    • Physics, Northeastern University, Boston, MA, USA