Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Order-Disorder Transition in a Two-Layer Quantum Antiferromagnet   We have studied the antiferromagnetic order -- disorder transition occurring
at $T=0$ in a 2-layer quantum Heisenberg antiferromagnet as the inter-plane
coupling is increased. Quantum Monte Carlo results for the staggered structure
factor in combination with finite-size scaling theory give the critical ratio
$J_c = 2.51 \pm 0.02$ between the inter-plane and in-plane coupling constants.
The critical behavior is consistent with the 3D classical Heisenberg
universality class. Results for the uniform magnetic susceptibility and the
correlation length at finite temperature are compared with recent predictions
for the 2+1-dimensional nonlinear $\sigma$-model. The susceptibility is found
to exhibit quantum critical behavior at temperatures significantly higher than
the correlation length.

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The categories of this paper are: comp-gas
34
The categories of this paper are: chem-ph
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The categories of this paper are: adap-org
7
The categories of this paper are: hep-th
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The categories of this paper are: math-ph
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The categories of this paper are: solv-int
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The categories of this paper are: gr-qc
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The categories of this paper are: acc-phys
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The categories of this paper are: plasm-ph
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The categories of this paper are: q-alg
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The categories of this paper are: econ
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The categories of this paper are: atom-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: supr-con
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The categories of this paper are: alg-geom
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The categories of this paper are: chao-dyn