China performs quantum messaging over longer distances

Monday, November 13, 2017

Chinese scientists have announced that they have made a major breakthrough in quantum communications, claiming to successfully transmit data via a quantum channel over a distance of 2.7 kilometres, according to a report by Defense One.

If the claim is verified, it will mark a significant milestone in quantum communication methods — sending messages that cannot be intercepted or spied on.

Quantum-encrypted data cannot be eavesdropped because a third party tampering with the communication channel causes a quantum message to change, and both the recipient and the sender will know that someone is attempting an intercept. Due to the nature of quantum physics, any observation using large-scale instruments influences — and so alters — the object of observation, an effect known as the Heisenberg Uncertainty Principle.

Much like the 20th century space race, the US and China are rapidly developing quantum messaging technology, and China appears to be in the lead, for now. In June, Chinese scientists demonstrated their first secure quantum communication by means of a small-scale tabletop experiment.

This time, they have pushed the boundaries by successfully sending and receiving sending quantum-based messages over much longer long distances. 

The Chinese research team claims that their system can be scaled to send messages "tens of kilometres".

If quantum communication becomes the new norm, it will alleviate the need for any form of encryption. While today's best encryption is nearly unbreakable, it is not 100-percent secure. Thus, developing quantum systems becomes a matter of national security.

In 2015, scientists from US Institute of Standards and Technology (NIST) teleported a photon over a 60-mile fiber-optic cable. 

"This is clearly a long way from a true communication medium, but it gets us closer to the possibility of quantum encryption," Extreme Tech wrote at the time.

This year, Chinese scientists leapt ahead by claiming to have teleported quants a whopping 1 200 kilometres distance, using a satellite.

The latest experiment, if not the farthest, did, however, include full-scale communication, including a security test, information encoding, fibre transmission and decoding, according to the authors of the paper. - Sputnik