Scientists have used quantum teleportation to send information over long distances, with a higher fidelity than ever before.
Quantum entanglement is a strange phenomenon that sounds like science fiction to our classical-physics-focused minds. Basically, two or more particles can become so entwined that changing the state of one instantly changes that of its partners – no matter how far apart they are.
This mechanism – which Einstein himself dubbed "spooky" – can be tapped into to create quantum networks. Pairs of photons can be entangled and separated, allowing data to be "teleported" between them over long distances. As a bonus, these networks could be more secure, since any hackers would garble the data just by trying to read it.
Now, researchers at Fermilab, AT&T, Caltech, Harvard, NASA JPL and the University of Calgary have demonstrated sustained, very accurate quantum teleportation over long distances. The team sent information over 44 km (27 miles) with fidelity of over 90 percent – an accuracy record for this distance.
To do so, the team added a third "node" in the middle, between the sender and receiver. To get information from A to B, both parties first send a photon to C. The receiver, B, sends one member of an entangled pair and keeps the other. When A and B's photons meet at C, they are then entangled, so that the information from A's photon is transferred to both of B's photons – the one it sent and the one it kept – thanks to the quantum entanglement link. In effect, it's basically the same as teleporting information from A to B.