Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Polarization-entangled photon pair sources based on spontaneous four
  wave mixing assisted by polarization mode dispersion   Photonic-based qubits and integrated photonic circuits have enabled
demonstrations of quantum information processing (QIP) that promises to
transform the way in which we compute and communicate. To that end, sources of
polarization-entangled photon pair states are an important enabling technology,
especially for polarization-based protocols. However, such states are difficult
to prepare in an integrated photonic circuit. Scalable semiconductor sources
typically rely on nonlinear optical effects where polarization mode dispersion
(PMD) degrades entanglement. Here, we directly generate polarization-entangled
states in an AlGaAs waveguide, aided by the PMD and without any compensation
steps. We perform quantum state tomography and report a raw concurrence as high
as 0.91$\pm$0.01 observed in the 1100-nm-wide waveguide. The scheme allows
direct Bell state generation with an observed maximum fidelity of 0.90$\pm$0.01
from the 800-nm-wide waveguide. Our demonstration paves the way for sources
that allow for the implementation of polarization-encoded protocols in
large-scale quantum photonic circuits.

32
The categories of this paper are: atom-ph
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
22
The categories of this paper are: chao-dyn
23
The categories of this paper are: solv-int
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
25
The categories of this paper are: patt-sol
7
The categories of this paper are: hep-th
21
The categories of this paper are: adap-org
15
The categories of this paper are: nucl-ex
36
The categories of this paper are: cmp-lg
27
The categories of this paper are: comp-gas