Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the effects of self- and cross-phase modulation on photon purity for
  four-wave mixing photon-pair sources   We consider the effect of self-phase modulation and cross-phase modulation on
the joint spectral amplitude of photon pairs generated by spontaneous four-wave
mixing. In particular, the purity of a heralded photon from a pair is
considered, in the context of schemes that aim to maximise the purity and
minimise correlation in the joint spectral amplitude using birefringent
phase-matching and short pump pulses. We find that non-linear phase modulation
effects will be detrimental, and will limit the quantum interference visibility
that can be achieved at a given generation rate. An approximate expression for
the joint spectral amplitude with phase modulation is found by considering the
group velocity walk-off between each photon and the pump, but neglecting the
group-velocity dispersion at each wavelength. The group-velocity dispersion can
also be included with a numerical calculation, and it is shown that it only has
a small effect on the purity for the realistic parameters considered.

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The categories of this paper are: cond-mat
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The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin
2
The categories of this paper are: math
28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
21
The categories of this paper are: adap-org
1
The categories of this paper are: cs
35
The categories of this paper are: mtrl-th
19
The categories of this paper are: eess
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
29
The categories of this paper are: funct-an
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The categories of this paper are: astro-ph
10
The categories of this paper are: q-bio