Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A polarization maintaining scheme for 1.5 {\mu}m polarization entangled
  photon pair generation in optical fibers   In this paper, the generation of polarization entangled photon pairs at 1.5
{\mu}m is experimentally demonstrated utilizing a polarization maintaining
all-fiber loop, consisting of a piece of commercial polarization maintaining
fiber and a polarization beam splitter/combiner with polarization maintaining
fiber pigtails. A quantum state tomography measurement is performed to analyze
the entanglement characteristic of the generated quantum state. In the
experiment, a polarization entangled Bell state is generated with a
entanglement fidelity of 0.97+/-0.03 and a purity of 0.94+/-0.03 demonstrating
that the proposed scheme can realize polarization entangled photon pair
generation with polarization maintaining property which is desired in
applications of quantum communication and quantum information.

9
The categories of this paper are: nlin
33
The categories of this paper are: plasm-ph
0
The categories of this paper are: hep-ph
19
The categories of this paper are: eess
29
The categories of this paper are: funct-an
12
The categories of this paper are: nucl-th
7
The categories of this paper are: hep-th
36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
3
The categories of this paper are: physics
27
The categories of this paper are: comp-gas
22
The categories of this paper are: chao-dyn
28
The categories of this paper are: alg-geom
18
The categories of this paper are: econ
26
The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci