Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Coulomb Driven New Bound States at the Integer Quantum Hall States in
  GaAs/Al(0.3)Ga(0.7)As Single Heterojunctions   Coulomb driven, magneto-optically induced electron and hole bound states from
a series of heavily doped GaAs/Al(0.3)Ga(0.7)As single heterojunctions (SHJ)
are revealed in high magnetic fields. At low magnetic fields (nu > 2), the
photoluminescence spectra display Shubnikov de-Haas type oscillations
associated with the empty second subband transition. In the regime of the
Landau filling factor nu < 1 and 1 < nu <2, we found strong bound states due to
Mott type localizations. Since a SHJ has an open valence band structure, these
bound states are a unique property of the dynamic movement of the valence holes
in strong magnetic fields.

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The categories of this paper are: astro-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: cmp-lg
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The categories of this paper are: bayes-an
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The categories of this paper are: chem-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: eess
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The categories of this paper are: math
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The categories of this paper are: alg-geom
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The categories of this paper are: stat
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The categories of this paper are: econ
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The categories of this paper are: q-fin
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The categories of this paper are: hep-th