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arXiv · 0709.3426

Raman imaging and electronic properties of graphene

F. Molitor·D. Graf·C. Stampfer·T. Ihn·K. Ensslin
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Abstract

Graphite is a well-studied material with known electronic and optical properties. Graphene, on the other hand, which is just one layer of carbon atoms arranged in a hexagonal lattice, has been studied theoretically for quite some time but has only recently become accessible for experiments. Here we demonstrate how single- and multi-layer graphene can be unambiguously identified using Raman scattering. Furthermore, we use a scanning Raman set-up to image few-layer graphene flakes of various heights. In transport experiments we measure weak localization and conductance fluctuations in a graphene flake of about 7 monolayer thickness. We obtain a phase-coherence length of about 2 $μ$m at a temperature of 2 K. Furthermore we investigate the conductivity through single-layer graphene flakes and the tuning of electron and hole densities via a back gate.

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F. Molitor, D. Graf, C. Stampfer, T. Ihn, K. Ensslin. 2007-09-21. Raman imaging and electronic properties of graphene. https://doi.org/10.1007/978-3-540-74325-5_14

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