Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Superconductivity in Co-doped LaFeAsO   Here we report the synthesis and basic characterization of LaFe1-xCoxAsO for
several values of x. The parent phase LaFeAsO orders antiferromagnetically (TN
~ 145 K). Replacing Fe with Co is expected to both electron dope the system and
introduce disorder in the FeAs layer. For x = 0.05 antiferromagnetic order is
destroyed and superconductivity is observed at Tconset = 11.2 K. For x = 0.11
superconductivity is observed at Tc(onset) = 14.3 K, and for x = 0.15 Tc = 6.0
K. Superconductivity is not observed for x = 0.2 and 0.5, but for x = 1, the
material appears to be ferromagnetic (Tc ~ 56 K) as judged by magnetization
measurements. We conclude that Co is an effective dopant to induce
superconductivity. Somewhat surprisingly, the system appears to tolerate
considerable disorder in the FeAs planes.

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The categories of this paper are: supr-con
3
The categories of this paper are: physics
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
25
The categories of this paper are: patt-sol
15
The categories of this paper are: nucl-ex
13
The categories of this paper are: quant-ph
6
The categories of this paper are: astro-ph
35
The categories of this paper are: mtrl-th
23
The categories of this paper are: solv-int
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The categories of this paper are: atom-ph
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The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
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The categories of this paper are: comp-gas
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The categories of this paper are: eess