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arXiv · 1301.2727

Evidence for Disorder Induced Delocalization in Graphite

L. Casparis·A. Fuhrer·D. Hug·D. Kölbl·D. M. Zumbühl
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Abstract

We present electrical transport measurements in natural graphite and highly ordered pyrolytic graphite (HOPG), comparing macroscopic samples with exfoliated, nanofabricated specimens of nanometer thickness. The latter exhibit a very large c-axis resistivity $\rho_c$ -- much larger than expected from simple band theory -- and non-monotonic temperature dependence, similar to macroscopic HOPG, but in stark contrast to macroscopic natural graphite. A recent model of disorder-induced delocalization is consistent with our transport data. Furthermore, Micro-Raman spectroscopy reveals clearly reduced disorder in exfoliated samples and HOPG, as expected within the model -- therefore presenting further evidence for a novel paradigm of electronic transport in graphite.

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L. Casparis, A. Fuhrer, D. Hug, D. Kölbl, D. M. Zumbühl. 2013-01-12. Evidence for Disorder Induced Delocalization in Graphite. https://arxiv.org/abs/1301.2727

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