Secure metropolitan quantum networks move a step closer

Successful new field tests of a continuous-variable quantum key distribution (CV-QKD) system over commercial fiber networks could pave the way to its use in metropolitan areas.That is the key achievement from a joint team of Chinese scientists, published today in Quantum Science and Technology, which demonstrates CV-QKD transmission over commercial deployed fiber link with a distance of 50 kilometres.

Team leader and lead author, Prof. Hong Guo, from a joint team of Peking University and Beijing University of Posts and Telecommunications (PKU-BUPT joint team), Beijing, said: “CV-QKD provides, in principle, unconditional secret keys to protect people’s data—such as banking information, emails and passwords.

“It has attracted much attention in the past few years, because it uses standard telecom components that operate at , instead of specific quantum devices such as single photon detectors etc, and it has potentially much higher secret key rates. However, most previous long-distance CV-QKD demonstrations were only done in laboratory fiber, without the disturbances caused by the field environment.”…READ MORE