Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Optical Hall conductivity of systems with gapped spectral nodes   We calculate the optical Hall conductivity within the Kubo formalism for
systems with gapped spectral nodes, where the latter have a power-law
dispersion with exponent n. The optical conductivity is proportional to n and
there is a characteristic logarithmic singularity as the frequency approaches
the gap energy. The optical Hall conductivity is almost unaffected by thermal
fluctuations and disorder for n=1, whereas disorder has a stronger effect on
transport properties if n=2.

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The categories of this paper are: q-bio
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The categories of this paper are: patt-sol
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The categories of this paper are: hep-th
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The categories of this paper are: q-alg
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The categories of this paper are: alg-geom
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The categories of this paper are: nlin
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The categories of this paper are: mtrl-th
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The categories of this paper are: funct-an
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The categories of this paper are: solv-int
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The categories of this paper are: econ
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The categories of this paper are: astro-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: adap-org
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The categories of this paper are: math-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: chem-ph