Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: High transport critical current densities in textured Fe-sheathed
  Sr1-xKxFe2As2+Sn superconducting tapes   We report the realization of grain alignment in Sn-added Sr1-xKxFe2As2
superconducting tapes prepared by ex-situ powder-in-tube method. At 4.2 K, high
transport critical current densities Jc of 2.5x10^4 A/cm^2 (Ic = 180 A) in
self-field and 3.5x10^3 A/cm^2 (Ic = 25.5 A) in 10 T have been measured. These
values are the highest ever reported so far for Fe-based superconducting wires
and tapes. We believe the superior Jc in our tape samples are due to well
textured grains and strengthened intergrain coupling achieved by Sn addition.
Our results demonstrated an encouraging prospect for application of iron based
superconductors.

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The categories of this paper are: quant-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: physics
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The categories of this paper are: nucl-ex
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The categories of this paper are: adap-org
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The categories of this paper are: math-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: nlin
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The categories of this paper are: ao-sci
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The categories of this paper are: solv-int
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The categories of this paper are: q-fin
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The categories of this paper are: econ
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The categories of this paper are: gr-qc
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The categories of this paper are: hep-lat
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The categories of this paper are: mtrl-th
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The categories of this paper are: funct-an