Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Superconductivity below 2.5K in Nb0.25Bi2Se3 topological insulator
  single crystal
17
The categories of this paper are: q-fin
23
The categories of this paper are: solv-int
2
The categories of this paper are: math
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
15
The categories of this paper are: nucl-ex
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys
19
The categories of this paper are: eess
0
The categories of this paper are: hep-ph
6
The categories of this paper are: astro-ph
35
The categories of this paper are: mtrl-th
13
The categories of this paper are: quant-ph
18
The categories of this paper are: econ
12
The categories of this paper are: nucl-th