Quantum Computing Leap

Austrian and American scientists have for the first time demonstrated practical quantum teleportation -- a technique that could make possible extraordinarily powerful quantum computers -- according to two studies published in the journal Nature on Thursday.

Groups at the National Institute of Standards and Technology in Boulder, Colo., and the University of Innsbruck in Austria independently created new systems to transfer one atom’s “quantum state,” a complex host of characteristics, to a distant atom at the speed of light.

This advance brings scientists one step closer to computers that could perform almost unlimited numbers of calculations simultaneously, revolutionizing cryptography and communication.

Quantum teleportation only transfers information, not matter. “This is not ‘Beam me up, Scotty,’ ” said Rainer Blatt, head of the Innsbruck group.

The process exploits a bizarre effect called entanglement that Einstein called “spooky action at a distance.” When two particles are entangled, it’s as if their fates were linked. Even if they are great distances apart, without any physical connection, changes to one affect the other.

Entanglement is such a strange effect, even physicists wrestle with the idea. But David Wineland, director of the Boulder group, said, “Let’s not worry about it, let’s just use it.”

Both groups entangled two atoms using a third messenger atom to transfer the quantum state between them, and succeeded about 75% of the time, much more often than they could without using entanglement, he said.