Sagnac-type entangled photon source using only conventional polarization optics

Abstract We designed and implemented a novel combination of Sagnac-interferometer with Mach–Zehnder interferometer for source polarization-entangled photons. The new versatile configuration does not require multi-wavelength polarization optics, yet it performs good quality phase-stability over wide wavelength range. demonstrate the using only standard commercial optics to experimentally realize pulsed generation photon-pairs at wavelengths 764 nm 1221 via type-I spontaneous four-wave mixing in polarization-maintaining fiber. Polarization entanglement was verified by polarization-correlation measurement visibility 95.5% from raw coincidence counts violation Clauser–Horne–Shimony–Holt (CHSH) inequality S = 2.70 ± 0.04. long-term characterized an Allan deviation 8° integration time about 1 h no active phase-stabilization.