NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Efficient single-spatial-mode periodically-poled KTiOPO4 waveguide source for high-dimensional entanglement-based quantum key distribution
Published
Author(s)
Tian Zhong, Franco N. Wong, Alessandro Restelli, Joshua Bienfang
Abstract
We demonstrate generation of high-purity photon pairs at 1560 nm in a single spatial mode from a periodically-poled KTiOPO4 (PPKTP)waveguide. With nearly-lossless spectral filtering, the PPKTP waveguide source shows approximately 80 % single-mode fiber coupling efficiency and is well suited for high-dimensional time-energy entanglement-based quantum key distribution. Using high count-rate self-differencing InGaAs single-photon avalanche photodiodes configured with either square or sinusoidal gating, we achieve > 1 Mbit/s raw key generation with 3 bits-per-photon encoding, and, to the best of our knowledge, the highest reported Franson quantum-interference visibility of 98.2 % without subtraction of accidental coincidences.
Citation
Optics Express
Pub Type
Journals
Keywords
Photon Counting, Nonlinear optics, parametric processes, Quantum detectors, Quantum communications, Quantum information and processing.
Zhong, T.
, Wong, F.
, Restelli, A.
and Bienfang, J.
(2012),
Efficient single-spatial-mode periodically-poled KTiOPO4 waveguide source for high-dimensional entanglement-based quantum key distribution, Optics Express
(Accessed October 17, 2025)