Affordable Access

deepdyve-link deepdyve-link
Publisher Website

Generation of polarization entangled photon pairs at telecommunication wavelength using cascaded χ2 processes in a periodically poled LiNbO3 ridge waveguide.

Authors
  • Arahira, Shin
  • Namekata, Naoto
  • Kishimoto, Tadashi
  • Yaegashi, Hiroki
  • Inoue, Shuichiro
Type
Published Article
Journal
Optics Express
Publisher
The Optical Society
Publication Date
Aug 15, 2011
Volume
19
Issue
17
Pages
16032–16043
Identifiers
DOI: 10.1364/OE.19.016032
PMID: 21934967
Source
Medline
License
Unknown

Abstract

We report the generation of high-purity correlated photon-pairs and polarization entanglement in a 1.5 μm telecommunication wavelength-band using cascaded χ((2)):χ((2)) processes, second-harmonic generation (SHG) and the following spontaneous parametric down conversion (SPDC), in a periodically poled LiNbO(3) (PPLN) ridge-waveguide device. By using a PPLN module with 600%/W of the SHG efficiency, we have achieved a coincidence-to-accidental ratio (CAR) higher than 4000 at 7.45×10(-5) of the mean number of the photon-pair per pulse. We also demonstrated that the maximum reach of the CAR was truly dark-count-limited by the single-photon detectors used here. This indicates that the fake (noise) photons were negligibly small in this system, even though the photon-pairs, the Raman noise photons, and the pump photons were in the same wavelength band. Polarization entangled photon pairs were also generated by constructing a Sagnac-loop-type interferometer which included the PPLN module and an optical phase-difference compensator to observe maximum entanglement. We achieved two-photon interference visibilities of 99.6% in the H/V basis and 98.7% in the diagonal basis. The peak coincidence count rate was approximately 50 counts per second at 10(-3) of the mean number of the photon-pair per pulse.

Report this publication

Statistics

Seen <100 times