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arXiv · 1401.6027

Band gaps in incommensurable graphene on hexagonal boron nitride

Menno Bokdam·Taher Amlaki·Geert Brocks·Paul J. Kelly
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Abstract

Devising ways of opening a band gap in graphene to make charge-carrier masses finite is essential for many applications. Recent experiments with graphene on hexagonal boron nitride (h-BN) offer tantalizing hints that the weak interaction with the substrate is sufficient to open a gap, in contradiction of earlier findings. Using many-body perturbation theory, we find that the small observed gap is what remains after a much larger underlying quasiparticle gap is suppressed by incommensurability. The sensitivity of this suppression to a small modulation of the distance separating graphene from the substrate suggests ways of exposing the larger underlying gap.

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Menno Bokdam, Taher Amlaki, Geert Brocks, Paul J. Kelly. 2014-01-23. Band gaps in incommensurable graphene on hexagonal boron nitride. https://doi.org/10.1103/physrevb.89.201404

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