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arXiv · 1107.3241

Transport through graphene on SrTiO3

N. J. G. Couto·B. Sacepe·A. F. Morpurgo
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Abstract

We report transport measurements through graphene on SrTiO3 substrates as a function of magnetic field B, carrier density n, and temperature T. The large dielectric constant of SrTiO3 screens very effectively long-range electron-electron interactions and potential fluctuations, making Dirac electrons in graphene virtually non-interacting. The absence of interactions results in a unexpected behavior of the longitudinal resistance in the N=0 Landau level, and in a large suppression of the transport gap in nano-ribbons. The "bulk" transport properties of graphene at B=0T, on the contrary, are completely unaffected by the substrate dielectric constant.

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N. J. G. Couto, B. Sacepe, A. F. Morpurgo. 2011-07-16. Transport through graphene on SrTiO3. https://doi.org/10.1103/physrevlett.107.225501

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