Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Behavior of excitonic levels in symmetric and asymmetric double quantum
  wells in a magnetic field
12
The categories of this paper are: nucl-th
1
The categories of this paper are: cs
13
The categories of this paper are: quant-ph
24
The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
33
The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
10
The categories of this paper are: q-bio
5
The categories of this paper are: gr-qc
14
The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
36
The categories of this paper are: cmp-lg