Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Negative Magnetoresistance without Chiral Anomaly in Topological
  Insulators   An intriguing phenomenon in topological semimetals and topological insulators
is the negative magnetoresistance (MR) observed when a magnetic field is
applied along the current direction. A prevailing understanding to the negative
MR in topological semimetals is the chiral anomaly, which, however, is not well
defined in topological insulators. We calculate the MR of a three-dimensional
topological insulator, by using the semiclassical equations of motion, in which
the Berry curvature explicitly induces an anomalous velocity and orbital
moment. Our theoretical results are in quantitative agreement with the
experiments. The negative MR is not sensitive to temperature and increases as
the Fermi energy approaches the band edge. The orbital moment and g factors
also play important roles in the negative MR. Our results give a reasonable
explanation to the negative MR in 3D topological insulators and will be helpful
in understanding the anomalous quantum transport in topological states of
matter.

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The categories of this paper are: hep-ex
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The categories of this paper are: comp-gas
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The categories of this paper are: atom-ph
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The categories of this paper are: stat
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The categories of this paper are: patt-sol
3
The categories of this paper are: physics
33
The categories of this paper are: plasm-ph
29
The categories of this paper are: funct-an
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The categories of this paper are: hep-th
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The categories of this paper are: dg-ga
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The categories of this paper are: nucl-ex
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The categories of this paper are: math-ph
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The categories of this paper are: adap-org
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The categories of this paper are: nlin
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The categories of this paper are: astro-ph
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The categories of this paper are: cs