Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The resonant magnetic mode: a common feature of high-$T_C$
  superconductors   Inelastic neutron scattering experiments in high-$T_c$ cuprates have
evidenced a new magnetic excitation present in the superconducting state. In
particular, recent experiments on single layer Tl$_{2}$Ba$_{2}$CuO$_{6+\delta
}$, performed near optimum doping ($ T_{c} \sim 90$ K), provide evidence of a
sharp magnetic resonant mode below $ T_{c}$, similar to previous reports on the
YBCO and BSCCO bilayer systems. This result supports models that ascribe a key
role to magnetic excitations in the mechanism of superconductivity.

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The categories of this paper are: eess
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The categories of this paper are: econ
14
The categories of this paper are: math-ph
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
7
The categories of this paper are: hep-th
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The categories of this paper are: q-alg
1
The categories of this paper are: cs
8
The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph
37
The categories of this paper are: supr-con
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The categories of this paper are: q-fin
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The categories of this paper are: nlin
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The categories of this paper are: funct-an
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The categories of this paper are: mtrl-th