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arXiv · 1009.1103

Tilted potential induced coupling of localized states in a graphene nanoconstriction

M. R. Connolly·K. L. Chiu·A. Lombardo·A. Fasoli·A. C. Ferrari·D. Anderson·G. A. C. Jones·C. G. Smith
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Abstract

We use the charged tip of a low temperature scanning probe microscope to perturb the transport through a graphene nanoconstriction. Maps of the conductance as a function of tip position display concentric halos, and by following the expansion of the halos with back-gate voltage we are able to identify an elongated domain over the nanoconstriction where they originate. Amplitude modulations of the transmission resonances are correlated with the gradient of the tip-induced potential and we analyze this in terms of modified coupling between localized states.

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M. R. Connolly, K. L. Chiu, A. Lombardo, A. Fasoli, A. C. Ferrari, D. Anderson, G. A. C. Jones, C. G. Smith. 2010-09-07. Tilted potential induced coupling of localized states in a graphene nanoconstriction. https://doi.org/10.1103/physrevb.83.115441

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