Minyan Wang

Twin-field quantum key distribution (TF-QKD) elevates the secure key rate from a linear to a square-root dependence on channel loss while preserving measurement-device-independent security. This protocol is uniquely positioned to enable global-scale quantum networks, even under extreme channel loss. While the first free-space TF-QKD has been experimentally implemented recently, the next step would be extending such protocol to the satellite platform. Here, we comprehensively addressed the challenges of performing satellite-ground TF-QKD. The biggest challenge, the Doppler effect, owing to the fast movement of the satellite, was considered. By developing the technical of laser frequency control and clock synchronization, the Doppler frequency shift on the spectrum and the period of the optical pulse are experimentally simulated and compensated. TF-QKD was performed with such simulation and compensation. The network configuration and losses are also analyzed. Our result paves the way towards satellite-based TF-QKD.