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arXiv · 1308.5947

Shot Noise in Lithographically Patterned Graphene Nanoribbons

Z. B. Tan·A. Puska·T. Nieminen·F. Duerr·C. Gould·L. W. Molenkamp·B. Trauzettel·P. J. Hakonen
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Abstract

We have investigated shot noise and conductance of multi-terminal graphene nanoribbon devices at temperatures down to 50 mK. Away from the charge neutrality point, we find a Fano factor $F \approx 0.4$, nearly independent of the charge density. Our shot noise results are consistent with theoretical models for disordered graphene ribbons with a dimensionless scattering strength $K_0 \approx 10$ corresponding to rather strong disorder. Close to charge neutrality, an increase in $F$ up to $\sim 0.7$ is found, which indicates the presence of a dominant Coulomb gap possibly due to a single quantum dot in the transport gap.

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Z. B. Tan, A. Puska, T. Nieminen, F. Duerr, C. Gould, L. W. Molenkamp, B. Trauzettel, P. J. Hakonen. 2013-08-27. Shot Noise in Lithographically Patterned Graphene Nanoribbons. https://doi.org/10.1103/physrevb.88.245415

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