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arXiv · 1106.2192

Dependence of transport on adatom location for armchair-edge graphene nanoribbons

Xiongwen Chen·Kehui Song·Benhu Zhou·Haiyan Wang·Guanghui Zhou
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Abstract

We study the transport property for armchair-edge graphene nanoribbons (AGNRs) with an adatom coupling to a semi-infinite quantum wire. Using the nonequilibrium Green's function approach with tight-binding approximation, we demonstrate that the tunneling current through the system is sensitively dependent on both the AGNR width and adatom location. Interestingly, when the adatom locates onto a carbon atom in the 3$j$th chain from the edge of a metallic AGNR, the system shows a transmission gap accompanied by a threshold voltage in $I-V$ curve like a semiconducting AGNR. This effect may be useful in scanning tunneling microscopy experimental characterization on graphene samples.

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Xiongwen Chen, Kehui Song, Benhu Zhou, Haiyan Wang, Guanghui Zhou. 2011-06-11. Dependence of transport on adatom location for armchair-edge graphene nanoribbons. https://doi.org/10.1063/1.3555445

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