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arXiv · 1706.03594

Two-photon interference of polarization-entangled photons in a Franson interferometer

Heonoh Kim·Sang Min Lee·Osung Kwon·Han Seb Moon
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Abstract

We present two-photon interference experiments with polarization-entangled photon pairs in a polarization-based Franson-type interferometer. Although the two photons do not meet at a common beamsplitter, a phase-insensitive Hong-Ou-Mandel type two-photon interference peak and dip fringes are observed, resulting from the two-photon interference effect between two indistinguishable two-photon probability amplitudes leading to a coincidence detection. A spatial quantum beating fringe is also measured for nondegenerate photon pairs in the same interferometer, although the two-photon states have no frequency entanglement. When unentangled polarization-correlated photons are used as an input state, the polarization entanglement is successfully recovered through the interferometer via delayed compensation.

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Heonoh Kim, Sang Min Lee, Osung Kwon, Han Seb Moon. 2017-06-12. Two-photon interference of polarization-entangled photons in a Franson interferometer. https://doi.org/10.1038/s41598-017-06196-x

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