Entanglement swapping over 100 km optical fiber with independent entangled photon-pair sources
Qi-Chao Sun, Yang-Fan Jiang, Ya-Li Mao, Lixing You, Wei Zhang, Weijun Zhang, Xiao Qiang Jiang, Teng‐Yun Chen, Hao Li, Yidong Huang, Xianfeng Chen, Zhen Wang, Jingyun Fan, Qiang Zhang, Jian-Wei Pan · Optica · 2017
Realizing long-distance entanglement swapping with independent sources in the real-world condition is important for both future quantum networks and fundamental study of quantum theory. Currently, entanglement swapping over a few tens of kilometers of underground optical fiber has been achieved. However, future applications demand entanglement swapping over longer distances in more complicated environments. We exploit two independent 1-GHz-clock sequential time-bin entangled photon-pair sources; develop several automatic stability controls; and successfully implement a field test of entanglement swapping over an optical fiber link of more than 100 km, including coiled, underground, and suspended optical fibers. Our result verifies the feasibility of such technologies for long-distance quantum networks and for many interesting quantum information experiments.