Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Coexistence of Antiferromagnetism and Superconductivity in Iron-Based
  Superconductors   We theoretically investigate the coexistence of antiferromagnetism and
superconductivity in the iron-based superconductors by using the mean-field
theory for two- and three-orbital models. We find that both the s_{+-}-wave and
s_{++}-wave superconductivity can coexist with antiferromagnetism in the two
models. On Dirac Fermi surfaces emerging in the antiferromagnetic phase, a
superconducting-gap function has a node for s_{++} wave but is nodeless for
s_{+-} wave. On the other hand, the gap function on non-Dirac Fermi surfaces is
either nodeless or accidentally nodal, depending on the parameters of pairing
interaction, which is independent of pairing symmetry.

34
The categories of this paper are: chem-ph
25
The categories of this paper are: patt-sol
33
The categories of this paper are: plasm-ph
29
The categories of this paper are: funct-an
31
The categories of this paper are: ao-sci
2
The categories of this paper are: math
3
The categories of this paper are: physics
0
The categories of this paper are: hep-ph
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
32
The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph
11
The categories of this paper are: hep-lat
10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex