Enhanced Conductance Fluctuation by Quantum Confinement Effect in Graphene Nanoribbons*

Conductance fluctuations are usually unavoidable in graphene nanoribbons (GNR) due to the presence of disorder along its edges. By measuring the low-frequency noise in GNR devices, we find that the conductance fluctuations are strongly correlated with the density-of-states of GNR [1]. In single-layer GNR, the gate-dependence of noise shows peaks whose positions quantitatively match the subband positions in the band structures of GNR. This correlation provides a robust mechanism to electrically probe the band structure of GNR, especially when the subband structures are smeared out in conductance measurement.\\[4pt] [1]. G. Xu et al. Nano Lett. 2010, 10, 4590--4594.