Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Selective-area van der Waals epitaxy of h-BN/graphene heterostructures
  via He$^{+}$ irradiation-induced defect-engineering in 2D substrates
36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math
35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
1
The categories of this paper are: cs
9
The categories of this paper are: nlin
10
The categories of this paper are: q-bio
29
The categories of this paper are: funct-an
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex