Scientists in Austria and the United States say they have "teleported" the properties of one atom to another, an achievement that brings closer the dream of super-fast quantum computers.
Far from being the teleportation of "Star Trek" in which Captain Kirk, Spock and Bones get beamed from the starship Enterprise to a distant planet, the experiment is rather more prosaic.
It entails transferring the key signatures of one atom to another nearby, in closely controlled lab conditions.
But, the researchers say in Thursday's edition of British science weekly Nature, it marks a critical step towards next-generation computers able to handle far bigger and more complex loads than today's super-computers, and at many times their speed.
Quantum computers "could use central processing elements smaller than a cube of sugar to carry out massively complex computations that are currently impossible", said the US National Institute of Standards and Technology (NIST), which took part in the experiment.
They could be used to smash codes, revolutionise database searches and develop novel products such as fraud-proof digital signatures, it said.
These results "represent a significant step towards making quantum information processing a reality", said physicist Rainer Blatt of the University of Innsbruck.
The properties transferred in the experiment are the so-called quantum state of the atom - its energy, spin, motion, magnetic field and other physical properties.
The key lies in a phenomenon, first discussed in theory by Einstein and others nearly 70 years ago, called quantum entanglement.
Under this, two particles manipulated by a coherent source of light, such as a laser beam, can behave like psychic twins. Even if they are far apart, a disturbance to one particle affects the other - an oddity, called entanglement, that Einstein himself lyrically dubbed "spooky interaction".
The researchers used three positively-charged beryllium atoms that were trapped in a field of ions, and used lasers to manipulate their quantum states.
The first step was to "entangle" two of the atoms.
Their quantum properties were then precisely measured (doing so destroys the original quantum state) and those properties were then replicated by laser in the third atom, located eight microns (about a thousandth of an inch) away.
It took just four milliseconds to carry out this computer-controlled operation. Success rate was 78 percent.
The achievement marks progress towards storing, processing and retrieving data quickly.
Shunting and crunching "qubits" (quantum bits) of information will be the key as to whether quantum computing will ever happen or remain just a vision.
"It's hard to quickly move qubits to share or process information. But using teleportation as we've reported could allow logic operations to be performed much more quickly," David Wineland, a NIST physicist, said in a press release on Tuesday.
Quantum teleportation was first evoked in 1993 by an IBM researcher, Charles Bennett, who proposed using entanglement to transfer the quantum state of one atom to another.
But it took four years for the idea to become reality, with a couple of labs in Europe and the United States transporting a qubit, using entangled particles of light whose signature was sent down a fibre-optic cable and recreated at the other end.
The latest research takes that achievement a step further, for this is the first time that teleportation has involved atoms and that there has not been a physical link in the transfer.
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