Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Single Impurity Effects in Multiband Superconductors with Different Sign
  Order Parameters   A single impurity problem is investigated for multiband s-wave
superconductors with different sign order parameters (+-s-wave superconductors)
suggested in Fe-pnictide superconductors. Not only intraband but also interband
scattering is considered at the impurity. The latter gives rise to
impurity-induced local boundstates close to the impurity. We present an exact
form of the energy of the local boundstates as a function of strength of the
two types of impurity scattering. The essential role of the impurity is
unchanged in finite number of impurities. The main conclusions for a single
impurity problem help us understand effects of dense impurities in the +-s-wave
superconductors. Local density of states around the single impurity is also
investigated. We suggest impurity site nuclear magnetic resonance as a suitable
experiment to probe the local boundstates that is peculiar to the +-s-wave
state. We find that the +-s-wave model is mapped to a chiral dx2-y2+-idxy-wave,
reflecting the unconventional nature of the sign reversing order parameter. For
a quantum magnetic impurity, interband scattering destabilizes the Kondo
singlet.

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The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
34
The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci
20
The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
6
The categories of this paper are: astro-ph
32
The categories of this paper are: atom-ph
7
The categories of this paper are: hep-th