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arXiv · 1202.3327

Possible superconductivity in multi-layer-graphene by application of a gate voltage

A. Ballestar·P. Esquinazi·J. Barzola-Quiquia·S. Dusari·F. Bern·R. R. da Silva·Y. Kopelevich
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Abstract

The carrier density in tens of nanometers thick graphite samples (multi-layer-graphene, MLG) has been modified by applying a gate voltage ($V_g$) perpendicular to the graphene planes. Surface potential microscopy shows inhomogeneities in the carrier density ($n$) in the sample near surface region and under different values of $V_g$ at room temperature. Transport measurements on different MLG samples reveal that under a large enough applied electric field these regions undergo a superconducting-like transition at $T \lesssim 17$ K. A magnetic field applied parallel or normal to the graphene layers suppresses the transition without changing appreciably the transition temperature.

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A. Ballestar, P. Esquinazi, J. Barzola-Quiquia, S. Dusari, F. Bern, R. R. da Silva, Y. Kopelevich. 2012-02-15. Possible superconductivity in multi-layer-graphene by application of a gate voltage. https://arxiv.org/abs/1202.3327

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