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arXiv · 0911.3832

Scanning gate microscopy of current-annealed single layer graphene

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

We have used scanning gate microscopy to explore the local conductivity of a current-annealed graphene flake. A map of the local neutrality point (NP) after annealing at low current density exhibits micron-sized inhomogeneities. Broadening of the local e-h transition is also correlated with the inhomogeneity of the NP. Annealing at higher current density reduces the NP inhomogeneity, but we still observe some asymmetry in the e-h conduction. We attribute this to a hole doped domain close to one of the metal contacts combined with underlying striations in the local NP.

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M. R. Connolly, K. L. Chiou, C. G. Smith, D. Anderson, G. A. C. Jones, A. Lombardo, A. Fasoli, A. C. Ferrari. 2009-11-20. Scanning gate microscopy of current-annealed single layer graphene. https://doi.org/10.1063/1.3327829

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