Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Gap nodes induced by coexistence with antiferromagnetism in iron-based
  superconductors   We investigate the pairing in iron pnictides in the coexistence phase, which
displays both superconducting and antiferromagnetic orders. By solving the
pairing problem on the Fermi surface reconstructed by long-range magnetic
order, we find that the pairing interaction necessarily becomes
angle-dependent, even if it was isotropic in the paramagnetic phase, which
results in an angular variation of the superconducting gap along the Fermi
surfaces. We find that the gap has no nodes for a small antiferromagnetic order
parameter M, but may develop accidental nodes for intermediate values of M,
when one pair of the reconstructed Fermi surface pockets disappear. For even
larger M, when the other pair of reconstructed Fermi pockets is gapped by
long-range magnetic order, superconductivity still exists, but the
quasiparticle spectrum becomes nodeless again. We also show that the
application of an external magnetic field facilitates the formation of nodes.
We argue that this mechanism for a nodeless-nodal-nodeless transition explains
recent thermal conductivity measurements of hole-doped Ba_{1-x}K_xFe_2As_2.
[J-Ph. Read et.al. arXiv:1105.2232].

31
The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
6
The categories of this paper are: astro-ph
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
23
The categories of this paper are: solv-int
34
The categories of this paper are: chem-ph
7
The categories of this paper are: hep-th
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
17
The categories of this paper are: q-fin
19
The categories of this paper are: eess
32
The categories of this paper are: atom-ph