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Phase-stable source of polarization-entangled photons using a polarization Sagnac interferometer

Taehyun Kim·Marco Fiorentino·Franco N. C. Wong
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Abstract

We demonstrate a simple, robust, and ultrabright parametric down-conversion source of polarization-entangled photons based on a polarization Sagnac interferometer. Bidirectional pumping in type-II phase-matched periodically poled KTiOPO4 yields a measured flux of 5 000 polarization-entangled pairs/s per mW of pump power in a 1-nm bandwidth at 96.8% quantum-interference visibility. The common-path arrangement of the Sagnac interferometer eliminates the need for phase stabilization for the biphoton output state.

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Taehyun Kim, Marco Fiorentino, Franco N. C. Wong. 2005-09-30. Phase-stable source of polarization-entangled photons using a polarization Sagnac interferometer. https://doi.org/10.1103/physreva.73.012316

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