Tunable band gap in twisted bilayer graphene
arXiv:2403.14387 · doi:10.1103/PhysRevB.105.115106
Abstract
At large commensurate angles, twisted bilayer graphene which holds even parity under sublattice exchange exhibits a tiny gap. Here, we point out a way to tune this tiny gap into a large gap. We start from comprehensive understanding of the physical origin of gap opening by density functional theory calculations. We reveal that the effective inter-layer hopping, intra-layer CDW, or inter-layer charge imbalance favors a gap. Then, on the basis of tight-binding calculations, we suggest that a periodic transverse inhomogeneous pressure, which can tune inter-layer hoppings in specific regions of the moie supercell, may open a gap of over ~meV, which is further confirmed by first-principles calculations. Our results provide a theoretical guidance for experiments to open a large gap in twisted bilayer graphene.
arXiv comment9 pages, 9 figures
References in corpus (28)
- Magic-angle graphene superlattices: a new platform for unconventional superconductivity
- Correlated Insulator Behaviour at Half-Filling in Magic Angle Graphene Superlattices
- Wannier90: A Tool for Obtaining Maximally-Localised Wannier Functions
- Maximally localized Wannier functions: Theory and applications
- A Higher-Accuracy van der Waals Density Functional
- The GW method
- Gate-induced insulating state in bilayer graphene devices
- Superconductors, Orbital Magnets, and Correlated States in Magic Angle Bilayer Graphene
- Graphene bilayer with a twist: electronic structure
- Tunable Moiré Bands and Strong Correlations in Small-Twist-Angle Bilayer Graphene
- Origin of Mott insulating behavior and superconductivity in twisted bilayer graphene
- Commensuration and Interlayer Coherence in Twisted Bilayer Graphene
- Electronic structure of turbostratic graphene
- First direct observation of a nearly ideal graphene band structure
- Electronic properties of graphene-based bilayer systems
- Superlattice-induced insulating states and valley-protected orbits in twisted bilayer graphene
- Higher-Order Topological Insulator in Twisted Bilayer Graphene
- Pressure dependence of the magic twist angle in graphene superlattices
- Band Symmetries and Singularities in Twisted Multilayer Graphene
- Electronic spectrum of twisted bilayer graphene
- Interlayer coupling in rotationally faulted multilayer graphenes
- Externally controlled band gap in twisted bilayer graphene
- Single-electron gap in the spectrum of twisted bilayer graphene
- Topological crystalline insulator phase in graphene multilayers
- Pressure induced magnetism in rotated graphene bilayers
- Crystal Field Effect and Electric Field Screening in Multilayer Graphene with and without Twist
- Strain impacts on commensurate bilayer graphene superlattices: distorted trigonal warping, emergence of bandgap and direct-indirect bandgap transition
- Layer breathing and shear modes in multilayer graphene: A DFT-vdW study