Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Topological spin Hall states, charged skyrmions, and superconductivity
  in two dimensions   We study the properties of two dimensional topological spin hall insulators
which arise through spontaneous breakdown of spin symmetry in systems that are
spin rotation invariant. Such a phase breaks spin rotation but not time
reversal symmetry and has a vector order parameter. Skyrmion configurations in
this vector order parameter are shown to have electric charge that is twice the
electron charge. When the spin Hall order is destroyed by condensation of
skyrmions superconductivity results. This may happen either through doping or
at fixed filling by tuning interactions to close the skyrmion gap. In the
latter case the superconductor- spin Hall insulator quantum phase transition
can be second order even though the two phases break distinct symmetries.

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The categories of this paper are: chao-dyn
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The categories of this paper are: funct-an
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The categories of this paper are: comp-gas
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The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
13
The categories of this paper are: quant-ph
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The categories of this paper are: q-fin
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The categories of this paper are: nucl-ex
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The categories of this paper are: econ
10
The categories of this paper are: q-bio
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-lat
14
The categories of this paper are: math-ph
20
The categories of this paper are: acc-phys
33
The categories of this paper are: plasm-ph