Three-color Sagnac source of polarization-entangled photon pairs

Michael Hentschel (Corresponding author), Hannes Hübel, Andreas Poppe, Anton Zeilinger

Publications: Contribution to journalArticlePeer Reviewed


We demonstrate a compact and stable source of polarizationentangled pairs of photons, one at 810 nm wavelength for high detection efficiency and the other at 1550 nm for long-distance fiber communication networks. Due to a novel Sagnac-based design of the interferometer no active stabilization is needed. Using only one 30 mm ppKTP bulk crystal the source produces photons with a spectral brightness of 1.13 × 106 pairs/s/mW/THz with an entanglement fidelity of 98.2%. Both photons are single-mode fiber coupled and ready to be used in quantum key distribution (QKD) or transmission of photonic quantum states over large distances.
Original languageEnglish
Pages (from-to)23153-23159
Number of pages7
JournalOptics Express
Issue number25
Publication statusPublished - 2009

Austrian Fields of Science 2012

  • 103026 Quantum optics

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