Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Ring-shaped luminescence patterns in a locally photoexcited
  electron-hole bilayer
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg
28
The categories of this paper are: alg-geom
34
The categories of this paper are: chem-ph
2
The categories of this paper are: math
11
The categories of this paper are: hep-lat
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
25
The categories of this paper are: patt-sol