Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Broadband pumped polarization entangled photon-pair source in a linear
  beam displacement interferometer   We experimentally demonstrate a source of polarization entangled photon-pairs
based on a single periodically-poled potassium titanyl phosphate (PPKTP)
crystal pumped with a broadband, free running laser diode.The crystal is placed
within a linear beam-displacement interferometer, and emits photon-pairs based
ontype-0 spontaneous parametric downconversion (SPDC). We observe pair rates of
0.56 Mpairs/s/mW in a single spatial mode with a polarization visibility of
97.7% over a spectral range of 100 nm. This experiment demonstrates a pathway
towards observing Gigacount rates of polarization entangled photon pairs by
using high-power free-running laser diodes with fast multiplexed detectors.

7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
2
The categories of this paper are: math
24
The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
15
The categories of this paper are: nucl-ex
3
The categories of this paper are: physics
33
The categories of this paper are: plasm-ph
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
11
The categories of this paper are: hep-lat
19
The categories of this paper are: eess