Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Field-domain spintronics in magnetic semiconductor multiple quantum
  wells
13
The categories of this paper are: quant-ph
2
The categories of this paper are: math
24
The categories of this paper are: dg-ga
8
The categories of this paper are: hep-ex
11
The categories of this paper are: hep-lat
20
The categories of this paper are: acc-phys
29
The categories of this paper are: funct-an
12
The categories of this paper are: nucl-th
32
The categories of this paper are: atom-ph
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
19
The categories of this paper are: eess
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
6
The categories of this paper are: astro-ph