Chinese Scientists Succeed in Entangling Quantum Memories Across 50 km of Fiber Optic Cable

(LiveScience) A team of scientists in China has linked quantum memories over more than 30 miles (50 kilometers) of fiber optic cable, beating the previous record by more than 40 times over. This feat is an important step toward a hack-proof internet, scientists said.
Jian-Wei Pan, a professor of physics at the University of Science and Technology of China in Hefei have already demonstrated the entanglement of light particles, or photons, over long distances through empty space. In 2017, his team entangled two photons separated by 746 miles (1,200 km) using an Earth-orbiting satellite relay named Micius.
In the new study, Pan and his colleagues succeeded in entangling quantum memories across 50 km of fiber optic cable. The previous record of separation between memories was 0.8 miles (1.3 km). In the new study’s experiment, the quantum memory is an ensemble of laser-cooled rubidium atoms trapped in a vacuum.
“Quantum teleportation is a way to transfer an unknown quantum state from one particle to another at a distant location, without sending the original particle itself,” Jian-Wei Pan, said in an interview about the recent success.