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arXiv · 0809.1162

Effect of high-k environment on charge carrier mobility in graphene

L. A. Ponomarenko·R. Yang·T. M. Mohiuddin·S. M. Morozov·A. A. Zhukov·F. Schedin·E. W. Hill·K. S. Novoselov·M. I. Katsnelson·A. K. Geim
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Abstract

It is widely assumed that the dominant source of scattering in graphene is charged impurities in a substrate. We have tested this conjecture by studying graphene placed on various substrates and in high-k media. Unexpectedly, we have found no significant changes in carrier mobility either for different substrates or by using glycerol, ethanol and water as a top dielectric layer. This suggests that Coulomb impurities are not the scattering mechanism that limits the mean free path currently attainable for graphene on a substrate.

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L. A. Ponomarenko, R. Yang, T. M. Mohiuddin, S. M. Morozov, A. A. Zhukov, F. Schedin, E. W. Hill, K. S. Novoselov, M. I. Katsnelson, A. K. Geim. 2008-09-06. Effect of high-k environment on charge carrier mobility in graphene. https://doi.org/10.1103/physrevlett.102.206603

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