Quantum Network Infrastructure

Abstract Global quantum state distribution has applications in many areas, one of which is global key distribution for secure communications in an era of the threat of quantum computing. Long‐distance quantum key distribution requires a global network of optical relay stations, ground stations, and quantum memories. In this study, why quantum memories should be operated in space as untrusted nodes is presented. In addition to quantum key distribution, quantum memories in space are an enabling technology for distributed quantum sensor systems. The requirements for distributed sensors are outlined and the current technology readiness level of relevant systems is referenced. Finally, the possibility of an emerging quantum internet, enabling the coherent combination of quantum computers around the world, is addressed.