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High-efficiency, ultra-low-noise all-fiber photon pair source



Shellee D. Dyer, Martin J. Stevens, Burm Baek, Sae Woo Nam


We demonstrate an all-fiber photon pair source with the highest coincidence-to-accidental ratio (CAR) reported to date in the fiber optic telecom C-band. We achieve this through careful optimization of pair production efficiency as well as careful characterization and minimization of all sources of background photons, including Raman generation in the nonlinear fiber, Raman generation in the single-mode fiber, and leakage of pump photons. We cool the nonlinear fiber to 4 K to eliminate most of the Raman scattering, and we reduce other noise photons through careful system design. This yields a CAR of 1300, which is a factor of 12 higher than previously reported results. Measured data agree well with theoretical predictions.
Optics Express


Nonlinear optics, fibers, Nonlinear optics, parametric processes, Quantum optics.


Dyer, S. , Stevens, M. , Baek, B. and Nam, S. (2008), High-efficiency, ultra-low-noise all-fiber photon pair source, Optics Express, [online], (Accessed June 19, 2024)


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Created June 20, 2008, Updated February 19, 2017