Quantum Info Encoded into Phase and Arrival time of Photons

Technical results.

Abstract computer communication design. The Darmstadt system uses a protocol in which quantum information is encoded in the phase and arrival time of the photons. 

Secure Communication with Light Particles

Technical University of Darmstadt (Germany),  May 25, 2022

Researchers at Germany's Technical University of Darmstadt and telecommunications company Deutsche Telekom have developed an eavesdropping-proof communication network based on quantum key distribution. The system facilitates quantum key exchange, providing several parties with a common random number to encrypt/decrypt messages that third parties cannot decode. The system distributes photons to users from a central source in order to calculate the random number and the digital key; quantum entanglement ensures the key's security. The scheme employs a protocol in which quantum information is encoded in the photons' phase and arrival times, protecting it from environmental disruptions. The resulting quantum network is scalable in terms of user numbers, and requires no trusted nodes to be resilient.  ... '