Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cluster meanfield approximation for the optical response of weakly doped
  semiconductor quantum wells   The calculation of the optical properties of doped semiconductor quantum
wells is an intricate many-body problem because of the dynamical response of
the excess carriers to the photogenerated valence band hole. At low densities,
however, where the main effect of the dynamical response is the formation of
trions, a simple cluster meanfield approximation can be effectively employed to
calculate the optical susceptibility.

27
The categories of this paper are: comp-gas
3
The categories of this paper are: physics
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
12
The categories of this paper are: nucl-th
5
The categories of this paper are: gr-qc
25
The categories of this paper are: patt-sol
8
The categories of this paper are: hep-ex
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
32
The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph
16
The categories of this paper are: stat
2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat