Global Quantum Communication via a Satellite Train

T ransferring quantum information between widely separated locations is necessary to develop a global quantum network. This project is hindered by the high photon loss inherent to long-distance fiber-based transmission—the default for photonic qubits. To get around this problem, researchers have demonstrated the transmission of a quantum signal via satellite instead (see Viewpoint: Paving the Way for Satellite Quantum Communications). Now Sumit Goswami of the University of Calgary, Canada, and Sayandip Dhara of the University of Central Florida show how quantum information could be relayed over large distances by a network of such satellites [1].