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arXiv · 2102.12632

Broadband Fiber-based Entangled Photon Pair Source at Telecom O-band

Changjia Chen·Calvin Xu·Arash Riazi·Eric Y. Zhu·Alexey V. Gladyshev·Peter G. Kazansky·Li Qian
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Abstract

In this letter, we report a polarization-entangled photon-pair source based on type-II spontaneous parametric down conversion at telecom O-band in periodically poled silica fiber (PPSF). The photon-pair source exhibits more than 130 nm (~24 THz) emission bandwidth centered at 1306.6 nm. The broad emission spectrum results in a short biphoton correlation time and we experimentally demonstrate a Hong-Ou-Mandel interference dip with a full width of 26.6 fs at half maximum. Owing to the low birefringence of the PPSF, the biphotons generated from type-II SPDC are polarization-entangled over the entire emission bandwidth, with a measured fidelity to a maximally entangled state greater than 95.4%. The biphoton source provides the broadest bandwidth entangled biphotons at O-band to our knowledge.

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Changjia Chen, Calvin Xu, Arash Riazi, Eric Y. Zhu, Alexey V. Gladyshev, Peter G. Kazansky, Li Qian. 2021-02-25. Broadband Fiber-based Entangled Photon Pair Source at Telecom O-band. https://doi.org/10.1364/ol.415409

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