In-fiber direct generation of entangled and hyper-entangled photon pairs

Abstract

Entangled photon pair sources are crucial and indispensable components in quantum applications. Entangled photon sources based on nonlinear crystals or waveguides require bulky free-space optics and precision alignment. In contrast, fiber-based entangled photon sources, where entangled photon pairs are directly generated in an optical fiber, make quantum technologies less costly, more practical and accessible, as well as compatible with telecom fiber network infrastructure. In this talk, we review the development of fiber-based entangled and hyper-entangled photon pair sources based on the periodically-poled silica fiber (PPSF). We demonstrate practical and high quality entanglement sources at room temperature, compact and alignment free. The technology has now been commercialized. My talk will reveal the key technological advantages of using PPSF as a nonlinear material for entangled photon generation, as well as remaining challenges. If time permits, I will also briefly discuss the applications of polarization-frequency hyper-entanglement and characterization of high-dimensional entanglement systems, including deriving entanglement witnesses using machine learning.

Biography

Li Qian is a Canada Research Chair and a professor at the Department of Electrical and Computer Engineering, University of Toronto, Canada. Her research focuses in both classical and quantum optics. In classical optics, her group develops advanced metrology and sensing systems. In quantum optics, Her research focuses on experimental quantum key distribution in fiber networks, and entanglement generation in periodically poled silica fibres. This technology has now been commercialized by OZ Optics. She is currently an editor of JOSA B, and has served on the committees of various conferences, including OFC, CLEO, QCRYPT, Photonics North, BGPP, etc. She has published over 200 journal and conference papers.