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arXiv · 1005.4403

Shot Noise Suppression and Hopping Conduction in Graphene Nanoribbons

R. Danneau·F. Wu·M. Y. Tomi·J. B. Oostinga·A. F. Morpurgo·P. J. Hakonen
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Abstract

We have investigated shot noise and conduction of graphene field effect nanoribbon devices at low temperature. By analyzing the exponential $I-V$ characteristics of our devices in the transport gap region, we found out that transport follows variable range hopping laws at intermediate bias voltages $1 < V_{bias} < 12$ mV. In parallel, we observe a strong shot noise suppression leading to very low Fano factors. The strong suppression of shot noise is consistent with inelastic hopping, in crossover from one- to two-dimensional regime, indicating that the localization length $l_{loc} < W$ in our nanoribbons.

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R. Danneau, F. Wu, M. Y. Tomi, J. B. Oostinga, A. F. Morpurgo, P. J. Hakonen. 2010-05-24. Shot Noise Suppression and Hopping Conduction in Graphene Nanoribbons. https://doi.org/10.1103/physrevb.82.161405

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