Phys.org August 16, 2022
Researchers in China have reported the establishment of post selected entanglement between two atomic quantum memories physically separated by 12.5 km. They created atom-photon entanglement in one node and sent the photon to a second node for storage via electromagnetically induced transparency. They harnessed low-loss transmission through a field-deployed fiber of 20.5 km by making use of frequency down-conversion and up-conversion. The final memory-memory entanglement was verified to have a fidelity of 90% via retrieving to photons. According to the researchers their experiment makes a significant step forward toward the realization of a practical metropolitan-scale quantum network…read more. TECHNICAL ARTICLE 1 , 2 Â
Image representing the nodes’ layout on a map. Credit: Luo et al.