According to the Chinese Academy of Sciences (CAS), China’s quantum experimental scientific satellite the Mozi, launched on August 16, 2016, has achieved quantum communication over a distance of more than 1,000 kilometers, a world first.
Scientists said quantum communication was based on what they called “entangled quantum” – the way that two particles can become “entangled”, meaning the state of one is mirrored by another even when they are separated and there is no detectable connection between the two.
Given quantum entanglement is weakened in fiber optics and in the atmosphere, quantum communication had never been achieved at a distance beyond 100 kilometers. By functioning in space, the Mozi used a method that is less vulnerable to such issues. In early August, the Mozi sent a pair of entangled quantum particles to two earth stations which are 1,200km away from each other. The two stations later connected to each other with the quantum.
Given transmission between particles could theoretically be 100 percent secure – it is impossible to duplicate a quantum state – the Mozi’s achievement is expected to help make China a world leader in network security.