Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Upper critical field anisotropy in BaFe2-xCoxAs2 single crystals
  synthesized without flux   The upper critical field was measured upto 12 T for three BaFe2-xCoxAs2
single crystals with estimated Co concentrations of x = 0.082, x = 0.117 and x
= 0.143. HC2 versus temperature was measured from temperature dependent
resistivity, for various applied magnetic fields, H || ab and H || c. The
[dHC2/dT]T=Tc, normalized with the corresponding TC, decreases with increasing
Co content, for both directions. The anisotropy {\gamma} defined as HC2 || ab /
HC2 || c shows a distinct increase with Co content, and its temperature
dependence shows a peak close to the TC. Magneto transport measurements, in the
spin density wave regions, showed significant negative MR for H || ab and
positive MR of H || c in the x = 0.082 sample. The implications of these
results are discussed.

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The categories of this paper are: ao-sci
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The categories of this paper are: eess
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-th
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The categories of this paper are: supr-con
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The categories of this paper are: astro-ph
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The categories of this paper are: q-bio
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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: nucl-ex
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The categories of this paper are: alg-geom
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The categories of this paper are: nucl-th
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The categories of this paper are: solv-int
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The categories of this paper are: comp-gas
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The categories of this paper are: q-fin
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The categories of this paper are: dg-ga