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arXiv · 1001.4735

Fast and slow edges in bilayer graphene nanoribbons: Tuning the transition from band- to Mott-insulator

Alberto Cortijo·Laszlo Oroszlany·Henning Schomerus
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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 V_{g}. In contrast to the gate-induced gap in the bulk, the interaction-induced gap depends non-monotonously on the on-site potential V.

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Alberto Cortijo, Laszlo Oroszlany, Henning Schomerus. 2010-01-26. Fast and slow edges in bilayer graphene nanoribbons: Tuning the transition from band- to Mott-insulator. https://doi.org/10.1103/physrevb.81.235422

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