Cortijo Fernandez, Alberto and Oroszlany, Laszlo and Schomerus, Henning (2010) Fast and slow edges in bilayer graphene nanoribbons : tuning the transition from band to Mott insulator. Physical review B, 81 (23): 235422. ISSN 1550-235X
Abstract
We show that gated bilayer graphene zigzag ribbons possess a fast and a slow edge, characterized by edge-state velocities that differ due to non-negligible next-nearest-neighbor hopping elements. By applying bosonization and renormalization group methods, we find that the slow edge can acquire a sizable interaction-induced gap, which is tunable via an external gate voltage Vg. In contrast to the gate-induced gap in the bulk, the interaction-induced gap depends nonmonotonously on the on-site potential V.