Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Fabrication of high-quality PMMA/SiO$_x$ spaced planar microcavities for
  strong coupling of light with monolayer WS$_2$ excitons
14
The categories of this paper are: math-ph
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
22
The categories of this paper are: chao-dyn
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
1
The categories of this paper are: cs
5
The categories of this paper are: gr-qc
18
The categories of this paper are: econ
7
The categories of this paper are: hep-th
29
The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con