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arXiv · 1405.4938

Clustered impurities and carrier transport in supported graphene

N. Sule·S. C. Hagness·I. Knezevic
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Abstract

We investigate the effects of charged impurity distributions and carrier-carrier interactions on electronic transport in graphene on SiO$_2$ by employing a self-consistent coupled simulation of carrier transport and electrodynamics. We show that impurity clusters of characteristic width 40--50 nm generate electron--hole puddles of experimentally observed sizes. In the conductivity versus carrier density dependence, the residual conductivity and the linear-region slope are determined by the impurity distribution, and the measured slope can be used to estimate the impurity density in experiment. Furthermore, we show that the high-density sublinearity in the conductivity stems from carrier-carrier interactions.

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N. Sule, S. C. Hagness, I. Knezevic. 2014-05-20. Clustered impurities and carrier transport in supported graphene. https://doi.org/10.1103/physrevb.89.165402

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