Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Entanglement formation and violation of Bell's inequality with a
  semiconductor single photon source   We report the generation of polarization-entangled photons, using a quantum
dot single photon source, linear optics and photodetectors. Two photons created
independently are observed to violate Bell's inequality. The density matrix
describing the polarization state of the postselected photon pairs is also
reconstructed, and agrees well with a simple model predicting the quality of
entanglement from the known parameters of the single photon source. Our scheme
provides a method to generate no more than one entangled photon pair per cycle,
a feature useful to enhance quantum cryptography protocols using entangled
photons.

6
The categories of this paper are: astro-ph
10
The categories of this paper are: q-bio
2
The categories of this paper are: math
4
The categories of this paper are: cond-mat
24
The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat
34
The categories of this paper are: chem-ph
28
The categories of this paper are: alg-geom
3
The categories of this paper are: physics
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
20
The categories of this paper are: acc-phys
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an