Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Growth of and optical emission from GaMnAs thin films grown by molecular
  beam epitaxy   GaMnAs thin films with different Mn doping concentrations were grown via
molecular beam epitaxy using a substrate temperature of 250 {\deg}C. The thin
films were investigated using photoluminescence (PL) measurements from 8 to 300
K. Transitions involving Mn acceptors were identified and a binding energy of
~0.1 eV was found. A Mn doping concentration dependent PL spectrum was found to
lend insight into the film quality at a local level. Temperature dependent PL
studies show that the doping related emissions drop faster in energy than other
peaks with increasing temperature, indicating that they are more sensitive to
changes in the surrounding environment.

11
The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin
7
The categories of this paper are: hep-th
21
The categories of this paper are: adap-org
12
The categories of this paper are: nucl-th
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
20
The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
28
The categories of this paper are: alg-geom
5
The categories of this paper are: gr-qc