A quantum cryptography key has been shared between Beijing and Vienna using a satellite – allowing the presidents of the Chinese Academy of Sciences and Austrian Academy of Sciences to communicate via a secure video link.
Quantum key distribution (QKD) promises unconditionally secure communication provided by fundamental laws of quantum mechanics. Current QKD systems suffer from range limitations either due to the earth’s curvature or attenuation in optical fibers. The Chinese and Austrian Academies of Science decided to jointly establish the required technologies and infrastuctures for a satellite based global quantum key distribution network. Here we present the proposed experiment as well as the proof-of-concept demonstrations conducted on a 143 km horizontal free-space link between the Canary Islands (Spain) and a 6 km horizontal link in Graz (Austria).
Quantum communication, based on the quantum physics, can provide information theoretical security. Building a global quantum network is one ultimate goal for the research of quantum information. Here, this talk will review the progress for quantum communication in China, including quantum key distribution over metropolitan area with untrustful relay, field test of quantum entanglement swapping over metropolitan network, the 2000 km quantum key distribution main trunk line, and satellite based quantum communication.