Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Phase-modulated shaping of narrowband type-I parametric down-converted
  photons   We present a general theoretical description of the temporal shaping of
narrowband noncollinear type-I down-converted photons using a spectral phase
filter with a symmetric phase distribution. By manipulating the spectral phase
of the signal or idler photon, we demonstrate control of the correlation time
and shape of the two-photon wave function with modulation frequency and
modulation depth of the phase distribution.

36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
21
The categories of this paper are: adap-org
24
The categories of this paper are: dg-ga
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
2
The categories of this paper are: math
8
The categories of this paper are: hep-ex
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The categories of this paper are: atom-ph
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The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: q-fin
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The categories of this paper are: econ
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The categories of this paper are: solv-int
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The categories of this paper are: supr-con