Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetic Superstructure in the Two-Dimensional Quantum Antiferromagnet
  SrCu2(BO3)2   We report the observation of magnetic superstructure in a magnetization
plateau state of SrCu2(BO3)2, a frustrated quasi-two-dimensional quantum spin
system. The Cu and B nuclear magnetic resonance (NMR) spectra at 35 mllikelvin
indicate an apparently discontinuous phase transition from uniform
magnetization to a modulated superstructure near 27 tesla, above which a
magnetization plateau at 1/8 of the full saturation has been observed.
Comparison of the Cu NMR spectrum and the theoretical analysis of a Heisenberg
spin model demonstrates the crystallization of itinerant triplets in the
plateau phase within a large rhomboid unit cell (16 spins per layer) showing
oscillations of the spin polarization. Thus we are now in possession of an
interesting model system to study a localization transition of strongly
interacting quantum particles.

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The categories of this paper are: patt-sol
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The categories of this paper are: math-ph
33
The categories of this paper are: plasm-ph
0
The categories of this paper are: hep-ph
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The categories of this paper are: econ
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The categories of this paper are: comp-gas
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The categories of this paper are: nucl-th
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The categories of this paper are: q-fin
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The categories of this paper are: hep-th
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The categories of this paper are: q-bio
2
The categories of this paper are: math
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The categories of this paper are: acc-phys
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The categories of this paper are: dg-ga
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The categories of this paper are: funct-an
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The categories of this paper are: chao-dyn
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The categories of this paper are: atom-ph