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arXiv · 0812.1577

Model for the magnetoresistance and Hall coefficient of inhomogeneous graphene

Rakesh P. Tiwari·D. Stroud
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Abstract

We show that when bulk graphene breaks into n-type and p-type puddles, the in-plane resistivity becomes strongly field dependent in the presence of a perpendicular magnetic field, even if homoge- neous graphene has a field-independent resistivity. We calculate the longitudinal resistivity ρ_{xx} and Hall resistivity ρ_{xy} as a function of field for this system, using the effective-medium approximation. The conductivity tensors of the individual puddles are calculated using a Boltzmann approach suit- able for the band structure of graphene near the Dirac points. The resulting resistivity agrees well with experiment, provided that the relaxation time is weakly field-dependent. The calculated Hall resistivity has the sign of the majority carrier and vanishes when there are equal number of n and p type puddles.

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Rakesh P. Tiwari, D. Stroud. 2008-12-08. Model for the magnetoresistance and Hall coefficient of inhomogeneous graphene. https://doi.org/10.1103/physrevb.79.165408

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