Random resistor network model of minimal conductivity in graphene

V. V. Cheianov; V. I. Falko; B. L. Altshuler; I. L. Aleiner

doi:10.1103/physrevlett.99.176801

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arXiv · 0706.2968

Random resistor network model of minimal conductivity in graphene

V. V. Cheianov·V. I. Falko·B. L. Altshuler·I. L. Aleiner

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Abstract

Transport in undoped graphene is related to percolating current patterns in the networks of {\em N-} and {\em P}-type regions reflecting the strong bipolar charge density fluctuations. Transmissions of the {\em P-N} junctions, though small, are vital in establishing the macroscopic conductivity. We propose a random resistor network model to analyze scaling dependencies of the conductance on the doping and disorder, the quantum magnetoresistance and the corresponding dephasing rate.

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V. V. Cheianov, V. I. Falko, B. L. Altshuler, I. L. Aleiner. 2007-06-22. Random resistor network model of minimal conductivity in graphene. https://doi.org/10.1103/physrevlett.99.176801

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