China presents ‘Quantum Magpie Bridge’ internationally to quadruple the speed of quantum communication

Updated:Jun 09,2021 10:35 AM Global Times

Chinese scientists have successfully presented an experimental demonstration of "quantum magpie bridge" for the first time internationally, with the speed of quantum communication increasing four-fold, Xinhua News Agency reported on Thursday.

Li Chuanfeng, Zhou Zongquan and other scientists from the Guo Guangcan academician team of the University of Science and Technology of China in Hefei, East China's Anhui Province, have successfully completed an experimental demonstration of heralded entanglement between absorptive quantum memories, and published the article in Nature Magazine Wednesday, according to an official post on the university's official website.

According to the article, two nodes are built separately by 3.5 meters as each contains a polarization-entangled photon-pair source and a solid-state quantum memory with bandwidth up to 1 gigahertz, and a joint Bell-state measurement in the middle station can herald the distribution of maximally entangled states between the two quantum memories successfully.

The two nodes are like Niu Lang and Zhi Nü, two figures in ancient Chinese fairy tale, who have the capacity to successfully establish entanglement and smooth communication without meeting each other with the help of the "Quantum Magpie Bridge," according to Xinhua, citing Zhou Zongquan.

The quantum nodes and channels demonstrated in the experiment are able to serve as an elementary link of a quantum repeater, read the article, adding that the wideband absorptive quantum memories used in the nodes which are compatible with deterministic entanglement sources and are capable of simultaneously supporting multiplexing, facilitating the introduction of the construction of practical construction of practical solid-state quantum repeaters and high-speed quantum networks.