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arXiv · 1010.1796

Enhanced Conductance Fluctuation by Quantum Confinement Effect in Graphene Nanoribbons

Guangyu Xu·Carlos M. Torres Jr.·Emil B. Song·Jianshi Tang·Jingwei Bai·Xiangfeng Duan·Yuegang Zhang·Kang L. Wang
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Abstract

Conductance fluctuation is 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 fluctuation is strongly correlated with the density-of-states of GNR. 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.

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Guangyu Xu, Carlos M. Torres Jr., Emil B. Song, Jianshi Tang, Jingwei Bai, Xiangfeng Duan, Yuegang Zhang, Kang L. Wang. 2010-10-08. Enhanced Conductance Fluctuation by Quantum Confinement Effect in Graphene Nanoribbons. https://doi.org/10.1021/nl1025979

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