Topological tunability from even-odd order parameter mixing of monolayer 1T-TiSe2 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.

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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