Gate-tunable antiferromagnetic Chern insulator in twisted bilayer transition metal dichalcogenides

Abstract

A series of recent experimental works on twisted MoTe${}_2$ homobilayers have unveiled an abundance of exotic states in this system. Valley-polarized quantum anomalous Hall states have been identified at hole doping of $\nu =-1$, and the fractional quantum anomalous Hall effect is observed at $\nu =-2/3$ and $\nu =-3/5$. In this work, we investigate the electronic properties of AA-stacked twisted bilayer MoTe${}_2$ at $\nu =-2$ by $k$-space Hartree-Fock calculations. We find that the phase diagram is qualitatively similar to the phase diagram of a Kane-Mele-Hubbard with staggered onsite potential. A noteworthy phase within the diagram is the antiferromagnetic Chern insulator, stabilized by the external electric field. We attribute the existence of this Chern insulator to an antiferromagnetic instability at a topological phase transition between the quantum spin hall phase and a band insulator phase. We highlight that the antiferromagnetic Chern insulator phase is most evident at a twist angle of approximately $4^{\circ }$. Our research proposes the potential of realizing a Chern insulator beyond $\nu =-1$, and contributes fresh perspectives on the interplay between band topology and electron-electron correlations in moiré superlattices.

References in corpus (4)

• Signatures of Fractional Quantum Anomalous Hall States in Twisted MoTe2 Bilayer
• Observation of Fractionally Quantized Anomalous Hall Effect
• Observation of integer and fractional quantum anomalous Hall effects in twisted bilayer MoTe2
• Spin liquid in twisted homobilayers group-VI gichalcogenides

Cited by in corpus (20)

• Interplay between topology and correlations in the second moiré band of twisted bilayer MoTe2
• Adiabatic Approximation and Aharonov-Casher Bands in Twisted Homobilayer TMDs
• Variational Mapping of Chern Bands to Landau Levels: Application to Fractional Chern Insulators in Twisted MoTe${}_2$
• Quantum Geometry Probed by Chiral Excitonic Optical Response of Chern Insulators
• Interacting phase diagram of twisted bilayer MoTe${}_2$ in magnetic field
• Intrinsic Dipole Hall effect in twisted MoTe${}_2$: magnetoelectricity and contact-free signatures of topological transitions
• Moiré Band Engineering in Twisted Trilayer WSe2
• Fractional Chern Insulator and Quantum Anomalous Hall Crystal in Twisted MoTe${}_2$
• Twistronics and moiré superlattice physics in 2D transition metal dichalcogenides
• Topological magnons and domain walls in twisted bilayer MoTe${}_2$
• Artificial moiré engineering for an ideal BHZ model
• Quantum Phases in Twisted Homobilayer Transition Metal Dichalcogenides
• Orbital Magnetization of Correlated States in Twisted Bilayer Transition Metal Dichalcogenides
• Candidate for a Fractional Topological Insulator in Twisted MoTe2
• Twisted Type-II Rashba Homobilayer: A Platform for Tunable Topological Flat Bands
• Incipient quantum spin Hall insulator under strong correlations
• Probing Non-Fermi-Liquid Behaviour of Composite Fermi Liquid via Efficient Thermal Simulations
• Doping-induced Quantum Anomalous Hall Crystals and Topological Domain Walls
• Symmetry-protected topological wire in a topological vacuum
• The antiferromagnetic Chern insulator phase in the Kane-Mele-Hubbard model