Band gap formation in commensurate twisted bilayer graphene/hBN moiré lattices
arXiv:2403.14393 · doi:10.1103/PhysRevB.109.155139
Abstract
We report on the investigation of periodic superstructures in twisted bilayer graphene (tBLG) van-der-Waals heterostructures, where one of the graphene layers is aligned to hexagonal boron nitride (hBN). Our theoretical simulations reveal that if the ratio of the resulting two moiré unit cell areas is a simple fraction, the graphene/hBN moiré lattice acts as a staggered potential, breaking the degeneracy between tBLG AA sites. This leads to additional band gaps at energies where a subset of tBLG AA sites is fully occupied. These gaps manifest as Landau fans in magnetotransport, which we experimentally observe in an aligned tBLG/hBN heterostructure. Our study demonstrates the identification of commensurate tBLG/hBN van-der-Waals heterostructures by magnetotransport, highlights the persistence of moiré effects on length scales of tens of nanometers, and represents an interesting step forward in the ongoing effort to realise designed quantum materials with tailored properties.
18 pages, 13 figures
References in corpus (32)
- Unconventional quantum Hall effect and Berry's phase of 2pi in bilayer graphene
- Moiré heterostructures as a condensed matter quantum simulator
- Lattice relaxation and energy band modulation in twisted bilayer graphenes
- Fractional Chern insulators in magic-angle twisted bilayer graphene
- Untying the insulating and superconducting orders in magic-angle graphene
- Cascade of electronic transitions in magic-angle twisted bilayer graphene
- Cascade of Phase Transitions and Dirac Revivals in Magic Angle Graphene
- Decoupling superconductivity and correlated insulators in twisted bilayer graphene
- Superlattice-induced insulating states and valley-protected orbits in twisted bilayer graphene
- Mapping the twist angle and unconventional Landau levels in magic angle graphene
- Electronic properties of graphene hexagonal boron nitride moiré superlattice
- Flavour Hund's Coupling, Correlated Chern Gaps, and Diffusivity in Moiré Flat Bands
- Hofstadter subband ferromagnetism and symmetry broken Chern insulators in twisted bilayer graphene
- Composite super-moiré lattices in double aligned graphene heterostructures
- Correlated Hofstadter Spectrum and Flavor Phase Diagram in Magic Angle Graphene
- Moiré Commensurability and the Quantum Anomalous Hall Effect in Twisted Bilayer Graphene on Hexagonal Boron Nitride
- Double moiré with a twist: super-moiré in encapsulated graphene
- Band structure of twisted bilayer graphene on hexagonal boron nitride
- Dielectric permittivity, conductivity and breakdown field of hexagonal boron nitride
- Transport spectroscopy of ultraclean tunable band gaps in bilayer graphene
- Evidence of orbital ferromagnetism in twisted bilayer graphene aligned to hexagonal boron nitride
- Mirror Symmetry Breaking and Lateral Stacking Shifts in Twisted Trilayer Graphene
- Electrical switching of a moiré ferroelectric superconductor
- Graphene quantum dot on boron nitride: Dirac cone replica and Hofstadter butterfly
- Long-range ballistic transport of Brown-Zak fermions in graphene superlattices
- Symmetry breaking and anomalous conductivity in a double moiré superlattice
- Electron-hole asymmetry and band gaps of commensurate double moire patterns in twisted bilayer graphene on hexagonal boron nitride
- Electronic properties of twisted bilayer graphene suspended and encapsulated with hexagonal boron nitride
- Symmetry breaking in the double moiré superlattices of relaxed twisted bilayer graphene on hexagonal boron nitride
- Raman imaging of twist angle variations in twisted bilayer graphene at intermediate angles
- Formation of artificial Fermi surfaces with a triangular superlattice on a conventional two dimensional electron gas
- Wannier Diagram and Brown-Zak Fermions of Graphene on Hexagonal Boron-Nitride