Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Model for the magnetoresistance and Hall coefficient of inhomogeneous
  graphene   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
\rho_{xx} and Hall resistivity \rho_{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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The categories of this paper are: funct-an
9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
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The categories of this paper are: q-alg
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The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
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The categories of this paper are: comp-gas
22
The categories of this paper are: chao-dyn
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The categories of this paper are: cmp-lg
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The categories of this paper are: supr-con
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The categories of this paper are: eess
6
The categories of this paper are: astro-ph
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The categories of this paper are: adap-org
14
The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th