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arXiv · 1310.6086

Non-Ohmic behavior of carrier transport in highly disordered graphene

Shun-Tsung Lo·Chiashain Chuang·R. K. Puddy·T. -M. Chen·C. G. Smith·C. -T. Liang
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Abstract

We report measurements of disordered graphene probed by both a high electric field and a high magnetic field. By apply a high source-drain voltage Vsd, we are able to study the current-voltage relation I-Vsd of our device. With increasing Vsd, a crossover from the linear I-Vsd regime to the non-linear one, and eventually to activationless-hopping transport occurs. In the activationless-hopping regime, the importance of Coulomb interactions between charged carriers is demonstrated. Moreover, we show that delocalization of carriers which are strongly localized at low T and at small Vsd occurs with the presence of high electric field and perpendicular magnetic field..

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Shun-Tsung Lo, Chiashain Chuang, R. K. Puddy, T. -M. Chen, C. G. Smith, C. -T. Liang. 2013-10-26. Non-Ohmic behavior of carrier transport in highly disordered graphene. https://doi.org/10.1088/0957-4484%2F24%2F16%2F165201

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