Abstract
Edge reconstruction modifies the electronic properties of finite graphene samples. We formulate a low-energy theory of the reconstructed zigzag edge by deriving the modified boundary condition to the Dirac equation. If the unit-cell size of the reconstructed edge is not a multiple of three with respect to the zigzag unit cell, valleys remain uncoupled and the edge reconstruction is accounted for by a single angular parameter . Dispersive edge states exist generically, unless . We compute from a microscopic model for the “reczag” reconstruction (conversion of two hexagons into a pentagon-heptagon pair), and show that it can be measured via the local density of states. In a magnetic field, there appear three distinct edge modes in the lowest Landau level, two of which are counterpropagating.
3 More- Received 5 September 2011
DOI:https://doi.org/10.1103/PhysRevB.84.195434
©2011 American Physical Society