Researchers
working at TU Delft's Kavli Institute of Nanoscience in the Netherlands
claim to have successfully transferred data via teleportation. By
exploiting the quantum phenomenon known as particle entanglement,
the team says it transferred information across a 3 m (10 ft) distance,
without the information actually traveling through the intervening
space.
"Entanglement is arguably the strangest and most intriguing consequence of the laws of quantum mechanics," said the head of the research project, Professor Ronald Hanson. "When two particles become entangled, their identities merge: their collective state is precisely determined, but the individual identity of each of the particles has disappeared. The entangled particles behave as one, even when separated by a large distance."
"Entanglement is arguably the strangest and most intriguing consequence of the laws of quantum mechanics," said the head of the research project, Professor Ronald Hanson. "When two particles become entangled, their identities merge: their collective state is precisely determined, but the individual identity of each of the particles has disappeared. The entangled particles behave as one, even when separated by a large distance."
As electrons in an atom exist in orbits around a nucleus – like the way
that the Earth spins on its axis – electrons also have "spin." When two
electrons are entangled (that is, when they interact physically) and
are then forcibly separated, the spin information on each becomes
opposite to the other; they are essentially turned into mirror images.
However – and this is the bit that Einstein found "creepy" in his
rejection of the entanglement theory – when one of the entangled
electrons has its spin direction changed by some means, the other
electron immediately reverses its own spin direction. The distance in
the Kavli Institute tests was 3 m (10 ft) but, theoretically, this
distance could have been hundreds of light years.
In this case, the team teleported information contained in one quantum
bit (or qubit, the quantum analog of a standard computer bit) to a
completely separate quantum bit, using specially-designed computer
chips. Each chip featured a synthetic diamond to contain the entangled
electrons and several nitrogen atoms. Data was then encoded for
transmission in the transmitting diamond’s nitrogen atom as alterations
of the spin of the electron. The electron in the receiver diamond then
showed the opposite of that manipulation at precisely the time that the
transmission was "sent."
"We use diamonds because 'mini prisons' for electrons are formed in
this material whenever a nitrogen atom is located in the position of one
of the carbon atoms," explained Hanson. "The fact that we're able to
view these miniature prisons individually makes it possible for us to
study and verify an individual electron and even a single atomic
nucleus. We're able to set the spin (rotational direction) of these
particles in a predetermined state, verify this spin and subsequently
read out the data."
One practical upshot of this work is the idea of a future quantum
network for communication – a quantum internet – between ultra-fast
quantum computers. This should also enable completely secure information
transfer, as eavesdropping will be fundamentally impossible in such a
network because quantum mechanics guarantees that measuring quantum data
affects that data, so any changes will be immediately recognized.
In future experiments, the TU Delft team is planning on increasing the
distance to more than 1,300 m (4,200 ft) with chips housed in several
buildings across the university campus. The researchers hope to be the
first to realize evidence to disprove Einstein’s rejection of the
entanglement theory.
The team's research was published in the journal Science.
The video below shows members of the TU Delft team explaining the proposed experiment.
Source: TU Delft
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