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arXiv · 0705.0103

Roughness of undoped graphene and its short-range induced gauge field

N. Abedpour·M. Neek-Amal·Reza Asgari·F. Shahbazi·N. Nafari·M. Reza Rahimi Tabar
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Abstract

We present both numerical and analytical study of graphene roughness with a crystal structure including $500 \times 500$ atoms. The roughness can effectively result in a random gauge field and has important consequences for its electronic structure. Our results show that its height fluctuations in small scales have scaling behavior with a temperature dependent roughness exponent in the interval of $ 0.6 < χ< 0.7 $. The correlation function of height fluctuations depends upon temperature with characteristic length scale of $ \approx 90 Å$ (at room temperature). We show that the correlation function of the induced gauge field has a short-range nature with correlation length of about $\simeq 2-3 Å$. We also treat the problem analytically by using the Martin-Siggia-Rose method. The renormalization group flows did not yield any delocalized-localized transition arising from the graphene roughness. Our results are in good agreement with recent experimental observations.

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N. Abedpour, M. Neek-Amal, Reza Asgari, F. Shahbazi, N. Nafari, M. Reza Rahimi Tabar. 2007-11-08. Roughness of undoped graphene and its short-range induced gauge field. https://doi.org/10.1103/physrevb.76.195407

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