arXiv.svg (5.58 kB)
Broadband Fiber-based Entangled Photon Pair Source at Telecom O-band
preprintposted on 2023-01-11, 22:07 authored by Changjia Chen, Calvin Xu, Arash Riazi, Eric Y. Zhu, Alexey V. Gladyshev, Peter G. Kazansky, Li Qian
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.