Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: 23Na and 75As NMR Studies on NaFeAs0.8P0.2 Single Crystals   We report our $^{23}$Na and $^{75}$As NMR studies on isovalent
phosphorus-doped NaFeAs$_{0.8}$P$_{0.2}$ ($T_c=$ 33 K) single crystals. Our
data suggest a dramatic enhancement of the electron density of states on the
Fermi surface, and a large residual electron density of state below $T_c$.
However, evidence of antiferromagnetic spin fluctuations is shown by the
spin-lattice relaxation rate. The penetration depth, revealed from $^{23}$Na
NMR linewidth, follows the universal Uemura relation in iron pnictides. These
observations suggest that the correlation effects are still important for the
superconductivity in the phosphorus doped sample, although the Fermi surface is
probably significantly changed upon doping.

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The categories of this paper are: bayes-an
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The categories of this paper are: hep-ex
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The categories of this paper are: econ
0
The categories of this paper are: hep-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: comp-gas
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The categories of this paper are: supr-con
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The categories of this paper are: q-bio
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The categories of this paper are: acc-phys
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The categories of this paper are: nlin
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The categories of this paper are: hep-lat
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The categories of this paper are: hep-th
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The categories of this paper are: gr-qc
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The categories of this paper are: plasm-ph
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The categories of this paper are: q-fin
6
The categories of this paper are: astro-ph