Mathematical breakthrough sets out rules for more effective teleportation
16 January 2013
New protocol advances solutions for more efficient teleportation - the transport of quantum information at the speed of light.
S. Strelchuk, M. Horodecki, J. Oppenheim
Generalized Teleportation and Entanglement Recycling
For the last ten years, theoretical physicists have shown that the intense connections generated between particles as established in the quantum law of ‘entanglement’ may hold the key to eventual teleportation of quantum information. Now, for the first time, researchers have worked out how entanglement could be ‘recycled’ to increase the efficiency of these connections. The research, announced today, has been published in the journal Physical Review Letters. Although the result could conceivably take us a step closer to sci-fi style teleportation in the future, the research is purely theoretical in nature.
The team have also devised a generalised form of teleportation, which allows for a wide variety of potential applications in quantum physics. Once considered impossible, in 1993 a team of scientists calculated that teleportation could work in principle using quantum laws. Quantum teleportation harnesses the ‘entanglement’ law to transmit particle-sized bites of information across potentially vast distances in an instant.
Entanglement involves a pair of quantum particles such as electrons or protons that are intrinsically bound together, retaining synchronisation between the two that holds whether the particles are next to each other or on opposing sides of a galaxy. Through this connection, quantum bits of information - qubits - can be relayed using only traditional forms of classical communication. Previous teleportation protocols, have fallen into one of two camps, those that could only send scrambled information requiring correction by the receiver, or more recently, “port-based” teleportation that doesn't require a correction, but needed an impractical amount of entanglement – each object sent would destroy the entangled state.
Now, physicists from Cambridge, University College London, and the University
of Gdansk have developed a protocol to provide an optimal solution in which the
entangled state is ‘recycled’, so that the gateway between particles holds for
the teleportation of multiple objects.
They have even devised a protocol in which multiple qubits can be teleported
simultaneously, although the entangled state degrades proportionally to the
amount of qubits sent in both cases.
“The first protocol consists of sequentially teleporting states, and the second
teleports them in a bulk,” said Sergii Strelchuck from Cambridge’s Department
of Applied Mathematics and Theoretical Physics, who led the research with
colleagues Jonathan Oppenheim of UCL and Michal Horodecki of the
University of Gdansk.
“We have also found a generalised teleportation technique which we hope will
find applications in areas such as quantum computation.”
Einstein famously loathed the theory of quantum entanglement, dismissing it as
“spooky action at a distance”. But entanglement has since been proven to be a
very real feature of our universe, and one that has extraordinary potential to
advance all manner of scientific endeavor.
“There is a close connection between teleportation and quantum computers, which
are devices which exploit quantum mechanics to perform computations which would
not be feasible on a classical computer,” said Strelchuck.
“Building a quantum computer is one of the great challenges of modern physics,
and it is hoped that the new teleportation protocol will lead to advances in
While this protocol is completely theoretical, last year a
team of Chinese scientists reported teleporting photons over 143km, breaking
previous records, and quantum entanglement is increasingly seen as an important
area of scientific investment. Teleportation of information carried by
single atoms is feasible with current technologies, but the teleportation of
large objects - such as Captain Kirk - remains in the realm of science
Adds Strelchuck: “Entanglement can be thought of as the fuel, which powers
teleportation. Our protocol is more fuel efficient, able to use entanglement
thriftily while eliminating the need for error correction.”
Particle or wave... Credit: Jurvetson from Flickr
Sergii Strelchuk at the
University of Cambridge: +44
(0)7575461510 or +44 (0)1223760367 firstname.lastname@example.org
Michal Horodecki at the University of Gdansk: email@example.com
Jonathan Oppenheim at University College London and Royal Society University Research Fellow: firstname.lastname@example.org