Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Superconductivity induced by spark erosion in ZrZn2   We show that the superconductivity observed recently in the weak itinerant
ferromagnet ZrZn2 [C. Pfleiderer et al., Nature (London) 412, 58 (2001)] is due
to remnants of a superconducting layer induced by spark erosion. Results of
resistivity, susceptibility, specific heat and surface analysis measurements on
high-quality ZrZn2 crystals show that cutting by spark erosion leaves a
superconducting surface layer. The resistive superconducting transition is
destroyed by chemically etching a layer of 5 microns from the sample. No
signature of superconductivity is observed in rho(T) of etched samples at the
lowest current density measured, J=675 Am-2, and at T < 45 mK. EDX analysis
shows that spark-eroded surfaces are strongly Zn depleted. The simplest
explanation of our results is that the superconductivity results from an alloy
with higher Zr content than ZrZn2.

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The categories of this paper are: nucl-ex
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The categories of this paper are: chem-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: dg-ga
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The categories of this paper are: quant-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: q-bio
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The categories of this paper are: astro-ph
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The categories of this paper are: q-fin
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The categories of this paper are: hep-lat
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The categories of this paper are: stat
37
The categories of this paper are: supr-con
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The categories of this paper are: adap-org