Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Spin-dependent electron-impurity scattering in two-dimensional electron
  systems
22
The categories of this paper are: chao-dyn
2
The categories of this paper are: math
9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
26
The categories of this paper are: bayes-an
16
The categories of this paper are: stat
6
The categories of this paper are: astro-ph
32
The categories of this paper are: atom-ph
24
The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
3
The categories of this paper are: physics
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph