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arXiv · 1111.4887

Scaling of the energy gap in pattern-hydrogenated graphene

Roberto Grassi·Tony Low·Mark Lundstrom
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Abstract

Recent experiments show that a substantial energy gap in graphene can be induced via patterned hydrogenation on an iridium substrate. Here, we show that the energy gap is roughly proportional to $\sqrt{N_{H}}/N_{C}$ when disorder is accounted for, where $N_H$ and $N_C$ denote concentration of hydrogen and carbon atoms, respectively. The dispersion relation, obtained through calculation of the momentum-energy resolved density of states, is shown to agree with previous angle-resolved photoemission spectroscopy results. Simulations of electronic transport in finite size samples also reveal a similar transport gap, up to 1eV within experimentally achievable $\sqrt{N_{H}}/N_{C}$ value.

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Roberto Grassi, Tony Low, Mark Lundstrom. 2011-11-21. Scaling of the energy gap in pattern-hydrogenated graphene. https://doi.org/10.1021/nl2017338

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