Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Mixed-State Effect on the Low-Energy Spin Dynamics in Optimally-doped
  Iron Pnictide Superconductors   Based on a phenomenological model with $s_{\pm}$ or s-wave pairing symmetry,
the mixed-state effect on the low-energy spin dynamics in optimally-doped iron
pnictide superconductors is studied by solving Bogoliubov-de Gennes equations.
Our results of the spin susceptibility at $\mathbf{q}=\mathbf{Q}$ in the
normal, superconducting and mixed states agree qualitatively with recent
neutron scattering experiments. We also propose that the field-induced
intensity change shows different behaviors between the $s_{\pm}$ and s-wave
symmetries in both momentum and real space, thus it can be used to distinguish
these two pairing symmetries.

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The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn
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The categories of this paper are: comp-gas
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The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin
1
The categories of this paper are: cs
15
The categories of this paper are: nucl-ex
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The categories of this paper are: atom-ph
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The categories of this paper are: ao-sci
24
The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
19
The categories of this paper are: eess