Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Experimental investigation of the optical spin selection rules in bulk
  Si and Ge/Si quantum dots
2
The categories of this paper are: math
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
13
The categories of this paper are: quant-ph
30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
35
The categories of this paper are: mtrl-th
19
The categories of this paper are: eess
8
The categories of this paper are: hep-ex