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arXiv · 0907.3661

Tunable Superconducting Phase Transition in Metal-Decorated Graphene Sheets

B. M. Kessler·C. O. Girit·A. Zettl·V. Bouchiat
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Abstract

Using typical experimental techniques it is difficult to separate the effects of carrier density and disorder on the superconducting transition in two dimensions. Using a simple fabrication procedure based on metal layer dewetting, we have produced graphene sheets decorated with a non-percolating network of nanoscale tin clusters. These metal clusters both efficiently dope the graphene substrate and induce long-range superconducting correlations. This allows us to study the superconducting transition at fixed disorder and variable carrier concentration. We find that despite structural inhomogeneity on mesoscopic length scales (10-100 nm), this material behaves electronically as a homogenous dirty superconductor. Our simple self-assembly method establishes graphene as an ideal tunable substrate for studying induced two-dimensional electronic systems at fixed disorder and our technique can readily be extended to other order parameters such as magnetism.

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B. M. Kessler, C. O. Girit, A. Zettl, V. Bouchiat. 2009-10-05. Tunable Superconducting Phase Transition in Metal-Decorated Graphene Sheets. https://doi.org/10.1103/physrevlett.104.047001

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