Disorder-induced gap behavior in graphene nanoribbons

By P. Gallagher, Kathryn L Todd, David Goldhaber-Gordon. 2009

163 citations recorded by the source corpus.

We study the transport properties of graphene nanoribbons of standardized 30 nm width and varying lengths. We find that the extent of the gap observed in transport as a function of Fermi energy in these ribbons (the ``transport gap'') does not have a strong dependence on ribbon length, while the extent of the gap as a function of source-drain voltage (the ``source-drain gap'') increases with increasing ribbon length. We anneal the ribbons to reduce the amplitude of the disorder potential and find that the transport gap both shrinks and moves closer to zero gate voltage. In contrast, annealing does not systematically affect the source-drain gap. We conclude that the transport gap reflects the overall strength of the background disorder potential, while the source-drain gap is sensitively dependent on its details. Our results support the model that transport in graphene nanoribbons occurs through quantum dots forming along the ribbon due to a disorder potential induced by charged impurities.

Subfields: Biomedical Engineering, Materials Chemistry

View Paper: https://www.semanticscholar.org/paper/21883d26a907d6451eeb4cdc2d4fbe3907bb7edb

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Biomedical Engineering

1. E. Hwang
2. E. Rossi
3. N. M. R. Peres
4. S. Adam
5. Franco Nori
6. A. Rozhkov
7. A. Huczko
8. S. Tiwari

In Materials Chemistry

1. E. Rossi
2. E. Hwang
3. S. Adam
4. N. M. R. Peres
5. Franco Nori
6. A. Rozhkov
7. A. Huczko
8. Ramesh Oraon

Citations in the corpus

• Electronic transport in two-dimensional graphene (2010, background): “Two recent and detailed experiments (Gallagher et al., 2010; Han et al., 2010) seem to suggest that a combination of these pictures might be at play (e.”
• Magical Allotropes of Carbon: Prospects and Applications (2016, background): “The electronic properties of GNRs can be explained in terms of tight bonding theory (TBT) or by Dirac approach.(245,246)”
• Colloquium: Graphene spectroscopy (2014, unknown): “6See Gallagher et al. (2010); Han et al. (2010, 2007); Liu et al. (2009); Oostinga et al. (2010); Stampfer et al. (2009); and Todd et al. (2008).”
• Electronic properties of mesoscopic graphene structures: Charge confinement and control of spin and charge transport (2011, background): “Recent experiments [113–116] on gated nanoribbons discovered that there is a Fermi energy interval where the conductance is suppressed, see Fig.”
• Colloquium: The transport properties of graphene: An introduction (2010, background): “As a last comment, we note that the important topics of edge disorder (Gallagher et al., 2010; Lewenkopf et al., 2008; Mucciolo et al., 2009) and Coulomb blockade in graphene nanoribbons are not considered in this Colloquium, since they have been considered elsewhere (Dubois et al., 2009).”