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Generation of ultrabright tunable polarization entanglement without spatial, spectral, or temporal constraints

Marco Fiorentino·Gaetan Messin·Christopher E. Kuklewicz·Franco N. C. Wong·Jeffrey H. Shapiro
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Abstract

The need for spatial and spectral filtering in the generation of polarization entanglement is eliminated by combining two coherently-driven type-II spontaneous parametric downconverters. The resulting ultrabright source emits photon pairs that are polarization entangled over the entire spatial cone and spectrum of emission. We detect a flux of $\sim$12 000 polarization-entangled pairs/s per mW of pump power at 90% quantum-interference visibility, and the source can be temperature tuned for 5 nm around frequency degeneracy. The output state is actively controlled by precisely adjusting the relative phase of the two coherent pumps.

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Marco Fiorentino, Gaetan Messin, Christopher E. Kuklewicz, Franco N. C. Wong, Jeffrey H. Shapiro. 2003-09-08. Generation of ultrabright tunable polarization entanglement without spatial, spectral, or temporal constraints. https://doi.org/10.1103/physreva.69.041801

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