Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Specific-heat evidence of the first-order superconducting transition in
  Sr2RuO4   We investigate the specific heat of ultra-pure single crystals of Sr2RuO4, a
leading candidate of a spin-triplet superconductor. We for the first time
obtained specific-heat evidence of the first-order superconducting transition
below 0.8 K, namely divergent-like peaks and clear hysteresis in the specific
heat at the upper critical field. The first-order transition occurs for all
in-plane field directions. The specific-heat features for the first-order
transition are found to be highly sensitive to sample quality; in particular,
the hysteresis becomes totally absent in a sample with slightly lower quality.
These thermodynamic observations provide crucial bases to understand the
unconventional pair-breaking effect responsible for the first-order transition.

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The categories of this paper are: q-alg
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The categories of this paper are: atom-ph
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The categories of this paper are: funct-an
16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas
21
The categories of this paper are: adap-org
15
The categories of this paper are: nucl-ex
36
The categories of this paper are: cmp-lg
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
31
The categories of this paper are: ao-sci
2
The categories of this paper are: math
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The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
18
The categories of this paper are: econ
13
The categories of this paper are: quant-ph