Abstract
Entanglement swapping forms a key concept in the realization of scalable quantum networks and large-scale quantum communication. For the practical implementation of entanglement swapping, completely autonomous entanglement sources and a joint Bell-state measurement (BSM) between two independent photons are essential. Here, we experimentally demonstrate entanglement swapping between two independent polarization-entangled photon-pair sources obtained via spontaneous four-wave mixing (SFWM) in a Doppler-broadened atomic ensemble of ${^{87}}{\rm Rb}$ atoms. From the joint BSM, we estimate the ${\rm S}$ parameter in the Clauser–Horne–Shimony–Holt (CHSH) form of Bell’s inequality and confirm the violation of the Bell–CHSH inequality by ${\rm S}={2.32} \pm {0.07}$ with 4.5 standard deviations. We believe that this work is an important step toward realizing practical scalable quantum networks.
© 2020 Optical Society of America
Full Article | PDF ArticleMore Like This
Taek Jeong and Han Seb Moon
Opt. Lett. 45(9) 2668-2671 (2020)
Jiho Park, Danbi Kim, Heonoh Kim, and Han Seb Moon
Opt. Lett. 44(15) 3681-3684 (2019)
Taek Jeong, Yoon-Seok Lee, Jiho Park, Heonoh Kim, and Han Seb Moon
Optica 4(10) 1167-1170 (2017)