Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Linear temperature dependence of conductivity in the "insulating" regime
  of dilute two-dimensional holes in GaAs   The conductivity of extremely high mobility dilute two-dimensional holes in
GaAs changes linearly with temperature in the insulating side of the
metal-insulator transition. Hopping conduction, characterized by an
exponentially decreasing conductivity with decreasing temperature, is not
observed when the conductivity is smaller than $e^{2}/h$. We suggest that
strong interactions in a regime close to the Wigner crystallization must be
playing a role in the unusual transport.

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The categories of this paper are: nucl-th
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The categories of this paper are: q-bio
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The categories of this paper are: acc-phys
1
The categories of this paper are: cs
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The categories of this paper are: hep-ex
5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
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The categories of this paper are: quant-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: q-alg
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The categories of this paper are: econ
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The categories of this paper are: hep-ph
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The categories of this paper are: physics
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The categories of this paper are: hep-lat