Chiral limit and origin of topological flat bands in twisted transition metal dichalcogenide homobilayers

Abstract

The observation of zero field fractional quantum Hall analogs in twisted transition metal dichalcogenides (TMDs) asks for a deeper understanding of what mechanisms lead to topological flat bands in two-dimensional heterostructures, and what makes TMDs an excellent platform for topologically ordered phases, surpassing twisted bilayer graphene. To this aim, we explore the chiral limits of massive Dirac theories applicable to $C_3$-symmetric moiré materials, and show their relevance for both bilayer graphene and TMD homobilayers. In the latter, the Berry curvature of valence bands leads to relativistic corrections of the moiré potential that promote band flattening, and permit a limit with exactly flat bands with nonzero Chern number. The relativistic corrections enter as a \emph{layer-orbit coupling}, analogous to spin-orbit coupling for relativistic Dirac fermions, which we show is non-negligible on the moiré scale. The Berry curvature of the TMD monolayers therefore plays an essential role in the flattening of moiré Chern bands in these heterostructures.

References in corpus (16)

• Fractional quantum Hall states at zero magnetic field
• Signatures of Fractional Quantum Anomalous Hall States in Twisted MoTe2 Bilayer
• Fractional quantum Hall effect in the absence of Landau levels
• Fractional Chern insulators in magic-angle twisted bilayer graphene
• Fractional Chern Insulator in Twisted Bilayer MoTe${}_2$
• Fractional quantum anomalous Hall states in twisted bilayer MoTe${}_2$ and WSe${}_2$
• Anomalous Hall metal and fractional Chern insulator in twisted transition metal dichalcogenides
• Pressure--enhanced fractional Chern insulators in moiré transition metal dichalcogenides along a magic line
• Ideal Chern bands are Landau levels in curved space
• Topological superconductivity in doped magnetic moiré semiconductors
• Pedestrian index theorem a la Aharonov-Casher for bulk threshold modes in corrugated multilayer graphene
• Existence of the first magic angle for the chiral model of bilayer graphene
• Bridging the small and large in twisted transition metal dicalcogenide homobilayers: a tight binding model capturing orbital interference and topology across a wide range of twist angles
• Chiral model of twisted bilayer graphene realized in a monolayer
• Attractive Haldane bilayers for trapping non-Abelian anyons
• A Generic Topological Criterion for Flat Bands in Two Dimensions

Cited by in corpus (30)

• A Microscopic Perspective on Moiré Materials
• Anomalous Hall Crystals in Rhombohedral Multilayer Graphene I: Interaction-Driven Chern Bands and Fractional Quantum Hall States at Zero Magnetic Field
• Theory of fractional Chern insulator states in pentalayer graphene moiré superlattice
• Non-Abelian Fractional Quantum Anomalous Hall States and First Landau Level Physics in Second Moiré Band of Twisted Bilayer MoTe2
• Adiabatic Approximation and Aharonov-Casher Bands in Twisted Homobilayer TMDs
• Sublattice structure and topology in spontaneously crystallized electronic states
• Theory of Generalized Landau Levels and Implication for non-Abelian States
• Halperin States of Particles and Holes in Ideal Time Reversal Invariant Pairs of Chern Bands and The Fractional Quantum Spin Hall Effect in Moiré MoTe${}_2$
• Variational Mapping of Chern Bands to Landau Levels: Application to Fractional Chern Insulators in Twisted MoTe${}_2$
• Bridging the small and large in twisted transition metal dicalcogenide homobilayers: a tight binding model capturing orbital interference and topology across a wide range of twist angles
• Higher vortexability: zero field realization of higher Landau levels
• "Quantum Geometric Nesting" and Solvable Model Flat-Band Systems
• Contrasting twisted bilayer graphene and transition metal dichalcogenides for fractional Chern insulators: an emergent gauge picture
• Designing topology and fractionalization in narrow gap semiconductor films via electrostatic engineering
• Twist-angle evolution of the intervalley-coherent antiferromagnet in twisted WSe${}_2$
• Hofstadter spectrum of Chern bands in twisted transition metal dichalcogenides
• Nonlocal Moments in the Chern Bands of Twisted Bilayer Graphene
• Efficient prediction of superlattice and anomalous miniband topology from quantum geometry
• Minimal Fractional Topological Insulator in half-filled conjugate moiré Chern bands
• Quantum Geometry and the Hidden Scales in Materials
• Attractive Haldane bilayers for trapping non-Abelian anyons
• Reentrant topological phases and spin density wave induced by 1D moiré potentials
• Characterization of fractional Chern insulator quasiparticles in twisted homobilayer MoTe${}_2$
• Reentrant topological phases and entanglement scalings in moiré-modulated extended Su-Schrieffer-Heeger Model
• Topologically protected flatness in chiral moiré heterostructures
• Fractional Chern insulator candidate in twisted bilayer checkboard lattice
• Quantum-geometric dipole: a topological boost to flavor ferromagnetism in flat bands
• Non-Abelian Chern band in rhombohedral graphene multilayers
• Localizing Transitions via Interaction-Induced Flat Bands
• Chern-Selective multi-valley Flat Bands in Twisted Mono-Bilayer and Mono-Trilayer MoTe${}_2$