Robust non-Abelian even-denominator fractional Chern insulator in twisted bilayer MoTe2

ORAL  · Invited

Abstract

Inspired by recent experimental progress of discovering new phases for higher filling number of hole bands, in this talk, I will present our recent studies regarding whether a robust incompressible quantum Hall liquid can be stabilized in the half-filled Chern band of twisted MoTe$_2$ bilayers. We use the continuum model with parameters relevant to twisted MoTe$_2$ bilayers and obtain three consecutive nearly flat Chern bands with the same Chern number. Crucially, when the second moir\'e miniband is half-filled, signatures of non-Abelian frctional quantum Hall state are found via exact diagonalization calculations, including the stable six-fold ground state degeneracy which grows more robust for larger lattice sizes and is consistent with an even-denominator FCI state. We further perform flux insertion simulations to reveal a 1/2 quantized many-body Chern number as direct evidence of topological order. Furthermore, the ground state density structure factors show no sharp peak, indicating no charge density wave order. These evidences signal the potential of realizing the non-Abelian state at zero magnetic field in twisted bilayer MoTe$_2$ at the fractional hole filling 3/2.

*This work was primarily supported by the U.S. Department of Energy, Office of Basic Energy Sciences under Grant No. DE-FG02-06ER46305 (F.C., D.N.S.). W.Z. was supported by NSFC (No. 12474144). W.W.L. was supported by Zhejiang Provincial Natural Science Foundation of China under Grant No. LQN25A040013.

Publication: Robust non-Abelian even-denominator fractional Chern insulator in twisted bilayer MoTe2, F Chen, WW Luo, W Zhu, DN Sheng,
Nature Communications 16 (1), 2115.

Presenters

  • Donna Sheng

    • California State University, Northridge

Authors

  • Donna Sheng

    • California State University, Northridge
  • Feng Chen

    • The Hamburg Centre for Ultrafast Imaging and Institute for Quantum Physics, University of Hamburg
  • Wei-Wei Luo

    • Zhejiang Institute of Photoelectronics \& Zhejiang Institute for Advanced Light Source, Zhejiang Normal University
  • Wei Zhu

    • School of Science, Westlake University