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Quantum conductance of graphene nanoribbons with edge defects

T. C. Li·Shao-Ping Lu
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Abstract

The conductance of metallic graphene nanoribbons (GNRs) with single defects and weak disorder at their edges is investigated in a tight-binding model. We find that a single edge defect will induce quasi-localized states and consequently cause zero-conductance dips. The center energies and breadths of such dips are strongly dependent on the geometry of GNRs. Armchair GNRs are much more sensitive to a vacancy than zigzag GNRs, but are less sensitive to a weak scatter. More importantly, we find that with a weak disorder, zigzag GNRs will change from metallic to semiconducting due to Anderson localization. But a weak disorder only slightly affects the conductance of armchair GNRs. The influence of edge defects on the conductance will decrease when the widths of GNRs increase.

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T. C. Li, Shao-Ping Lu. 2006-09-01. Quantum conductance of graphene nanoribbons with edge defects. https://doi.org/10.1103/physrevb.77.085408

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