Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Inverse participation ratio and localization in topological insulator
  phase transitions   Fluctuations of Hamiltonian eigenfunctions, measured by the inverse
participation ratio (IPR), turn out to characterize topological-band insulator
transitions occurring in 2D Dirac materials like silicene, which is
isostructural with graphene but with a strong spin-orbit interaction. Using
monotonic properties of the IPR, as a function of a perpendicular electric
field (which provides a tunable band gap), we define topological-like quantum
numbers that take different values in the topological-insulator and
band-insulator phases.

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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: gr-qc
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The categories of this paper are: hep-ex
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The categories of this paper are: acc-phys
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The categories of this paper are: econ
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The categories of this paper are: math-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: q-bio
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The categories of this paper are: funct-an
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The categories of this paper are: hep-lat
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The categories of this paper are: alg-geom
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The categories of this paper are: nucl-ex
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The categories of this paper are: cs
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The categories of this paper are: chem-ph
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The categories of this paper are: adap-org