Flat bands are typically associated with finely tuned moiré systems in two dimensions. Here we show that twist stacking faults in bulk rhombohedral graphite generically produce nearly flat interface bands governed by the interplay between the moiré periodicity and Zak phase topology. We identify a condition for the emergence of flat bands across the entire moiré Brillouin zone associated with the extent of nontrivial Zak phase in momentum space. Using complementary continuum and tight-binding approaches, we demonstrate the evolution of these interface states and their dominance near the Fermi level. We further show that the flat bands host tunable topological character, with disorder driving a controlled evolution, and predict that the disorder will eventually make the valley Chern number vanish.

Close

PrevNext

View figure in article

• Topological defects
• Graphene
• Interfaces
• Twisted heterostructures