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arXiv · 1007.1316

The Effect of Interactions on the Conductance of Graphene Nanoribbons

M. Bazzanella·P. Faccioli·E. Lipparini
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Abstract

We study the effects of the interaction between electrons and holes on the conductance G of quasi-one-dimensional graphene systems. We first consider as a benchmark the limit in which all interactions are negligible, recovering the predictions of the tight-binding approximation for the spectrum of the system, and the well-known result G=4 e^2/h for the lowest conductance quantum. Then we consider an exactly solvable field theoretical model in which the electro-magnetic interactions are effectively local. Finally, we use the effective field theory formalism to develop an exactly solvable model in which we also include the effect of non-local interactions. We find that such interactions turn the nominally metallic armchair graphene nanoribbon into a semi-conductor, while the short-range interactions lead to a correction to the G=4 e^2/h formula.

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M. Bazzanella, P. Faccioli, E. Lipparini. 2010-07-08. The Effect of Interactions on the Conductance of Graphene Nanoribbons. https://doi.org/10.1103/physrevb.82.205422

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