Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The resistive transition and Meissner effect in carbon nanotubes:
  Evidence for quasi-one-dimensional superconductivity above room temperature   It is well known that copper-based perovskite oxides rightly enjoy consensus
as high-temperature superconductors on the basis of two signatures: the
resistive transition and the Meissner effect. We show that the resistive
transitions in carbon nanotubes agree quantitatively with the
Langer-Ambegaokar-McCumber-Halperin (LAMH) theory for quasi-1D superconductors
although the superconducting transition temperatures can vary from 0.4 K to 750
K for different samples. We have also identified the Meissner effect in the
field parallel to the tube axis up to room temperature for aligned and
physically separated multi-walled nanotubes (MWNTs). The magnitude of the
Meissner effect is in quantitative agreement with the predicted penetration
depth from the measured carrier density. Furthermore, the bundling of
individual MWNTs into closely packed bundles leads to a large enhancement in
the diamagnetic susceptibility, which is the hallmark of the Josephson coupling
among the tubes in bundles. These results consistently indicate quasi-1D
high-temperature superconductivity in carbon nanotubes.

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The categories of this paper are: math
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The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
33
The categories of this paper are: plasm-ph
26
The categories of this paper are: bayes-an
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The categories of this paper are: hep-lat
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The categories of this paper are: dg-ga
16
The categories of this paper are: stat
3
The categories of this paper are: physics
17
The categories of this paper are: q-fin
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The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
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The categories of this paper are: alg-geom
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The categories of this paper are: patt-sol
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The categories of this paper are: astro-ph
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The categories of this paper are: q-alg