Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Single-crystal superconducting nanowires of NbSe$_2$ fabricated by
  reactive plasma etching   We present the preparation and measurements of nanowires of single-crystal
NbSe$_2$. These nanowires were prepared on ultrathin ($\lesssim10\text{ nm}$)
flakes of NbSe$_2$ mechanically exfoliated from a bulk single crystal using a
process combining electron beam lithography and reactive plasma etching. The
electrical contacts to the nanowires were prepared using Ti/Au. Our technique,
which overcomes several limitations of methods developed previously for
fabricating superconducting nanowires, also allows for the preparation of
complex superconducting nanostructures with a desired geometry. Current-voltage
characteristics of individual superconducting single-crystal nanowires with
widths down to 30~nm and cross-sectional areas as low as 270 nm$^2$ were
measured for the first time.

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The categories of this paper are: comp-gas
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The categories of this paper are: dg-ga
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The categories of this paper are: acc-phys
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The categories of this paper are: eess
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The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
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The categories of this paper are: funct-an
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The categories of this paper are: hep-ex
0
The categories of this paper are: hep-ph
1
The categories of this paper are: cs
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The categories of this paper are: plasm-ph
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The categories of this paper are: nlin
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: supr-con