Apparently, China has managed to make quantum “teleportation” work, using a blue laser over a range of 16km–thus paving the way for extra-secure communication. Basically, they used entangled particles: every modification to the state of one is reflected instantly in the other.
Pretty darn cool. No idea how close to feasible we are (probably further off than the article implies), but that’s a neat application of quantum physics.
The security of using quantum teleportation to distribute cryptographic keys, on the other hand, is upheld by the laws of physics and has a seemingly infinite time horizon. These keys cannot currently be detected and cracked even with the help of the most powerful computers. Owing to the Heisenberg Uncertainty Principle, the quantum states of photons cannot be observed without changing the state of the particle, which has the result of immediately informing the sender and receiver of any eavesdropping. Quantum communication can thus be used to send the most sensitive information, including keys to decode encrypted data sent over less secure means.
Aliette de Bodard is a Computer Engineer who lives and works in France. When not wrestling with Artificial Intelligence problems (aka teaching computers how to analyse what they see), she writes speculative fiction. She is the author of the Aztec fantasy Servant of the Underworld from Angry Robot, and has had short fiction published in Asimov’s, Interzone and the Year’s Best Science Fiction.