Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Disorder Induced Effects on the Critical Current Density of Iron
  Pnictide BaFe_1.8 Co_0.2 As_2 single crystals   Investigating the role of disorder in superconductors is an essential part of
characterizing the fundamental superconducting properties as well as assessing
potential applications of the material. In most cases, the information
available on the defect matrix is poor, making such studies difficult, but the
situation can be improved by introducing defects in a controlled way, as
provided by neutron irradiation. In this work, we analyze the effects of
neutron irradiation on a Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ single crystal. We
mainly concentrate on the magnetic properties which were determined by
magnetometry. Introducing disorder by neutron irradiation leads to significant
effects on both the reversible and the irreversible magnetic properties, such
as the transition temperature, the upper critical field, the anisotropy, and
the critical current density. The results are discussed in detail by comparing
them with the properties in the unirradiated state.

28
The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
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The categories of this paper are: eess
5
The categories of this paper are: gr-qc
21
The categories of this paper are: adap-org
17
The categories of this paper are: q-fin
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The categories of this paper are: solv-int
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The categories of this paper are: astro-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: quant-ph
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The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
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The categories of this paper are: stat