Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Functional Renormalization Group Analysis of $\eta$-Pairing in
  Iron-based Superconductors   Using functional renormalization group (FRG) approach, we analyze the $\eta$
pairing in a five d-orbital model for iron-pncitides. We find that the $\eta$
pairing between two hole pockets is a leading instability at low energy when
the two hole pockets are close to a nesting condition. The result suggests that
the system can spontaneously enter into a superconducting state with both
normal pairing and $\eta$ paring and the $\eta$ pairing is driven by the
inter-orbital antiferromagnetic exchange coupling while the normal pairing is
driven by the intra-orbital antiferromagnetic ones. An effective model at low
energy is proposed to account for the $\eta$ pairing instability.

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The categories of this paper are: plasm-ph
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
6
The categories of this paper are: astro-ph
19
The categories of this paper are: eess
9
The categories of this paper are: nlin
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: atom-ph
35
The categories of this paper are: mtrl-th
28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con