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An Optical Fiber-Based Source of Polarization-Entangled Photon Pairs



Jingyun Fan, M D. Eisaman, Alan L. Migdall


We describe an achromatic, phase-stable, broadband source of polarization-entangled photon pairs with high spectral brightness that uses four-wave mixing in a fiber Sagnac interferometer. We achieved a polarization-entangled two-photon coincidence rate of 7 kHz per 0.5 THz (0.9 nm) of bandwidth per 300 ?W of average pump power. At this rate, we observed two-photon fringe interference visibilities greater than 97%, over a 10 THz (? 24 nm) spectral range. We measured violations of Bell s inequality by more than 24 standard deviations for each of the four Bell states in less than 3 minutes per state. Our measurements demonstrate that this source possesses a high spectral brightness (7 kHz/300 ?W/0.9 nm), large tunable wavelength range (24 nm), single spatial mode, and phase stability, making it a promising candidate for a wide range of quantum-information applications.
Proceedings of SPIE


accidental, Bell state, coincidence, four-wave mixing, Raman scattering, Sagnac interferometer


Fan, J. , Eisaman, M. and Migdall, A. (2007), An Optical Fiber-Based Source of Polarization-Entangled Photon Pairs, Proceedings of SPIE, [online], (Accessed May 25, 2024)


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Created September 10, 2007, Updated February 19, 2017