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Optical Fiber Communication Conference

Telecom-band Hyperentangled Photon Pairs from a Fiber-based Source

Changjia Chen, Calvin Xu, Arash Riazi, Eric Y. Zhu, Alexander C. B. Greenwood, Alexey V. Gladyshev, Peter G. Kazansky, Brian T. Kirby, Li Qian

Published Jan 1, 2022• 1 citation
Publisher

Abstract

We experimentally demonstrate the generation of telecom-band biphotons hyperentangled in both the polarization and frequency DoFs using a periodically-poled silica fiber and observe entanglement concurrences above 0.95 for both DOFs.
DOI
10.1364/ofc.2022.th4b.2

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We treat spontaneous parametric downconversion in a periodically poled fiber, quasi-phase matched to allow for the generation of photon pairs at wavelengths within the low-loss telecommunications window. For an appropriate pump polarization, the unusual properties of such a fiber's effective chi(2) result in a biphoton wave function that is symmetric upon simultaneous exchange of downconverted photon frequencies and polarizations and that is nonzero over a wide range of downconverted frequencies. This could lead to a significant technical simplification of sources of in-fiber telecom-band polarization-entangled photons.
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