Stay up to date with notifications from The Independent

Notifications can be managed in browser preferences.

Beam me up, Scotty - one laser-beam encoded stream of information at a time

Tuesday 18 June 2002 00:00 BST
Comments

It's teleportation, Jim, but not as Star Trek fans know it. A team of scientists in Australia have managed to "teleport" a stream of information encoded in one laser beam and made it reappear in another beam a metre away using quantum physics.

The true value of the work will probably lie in creating super-secure communications channels for governments and financial institutions, as it is impossible to tap such quantum communications.

But Trekkies can still live in hope: the team leader, Dr Ping Koy Lam of the Australian National University in Canberra, reckons that in "the next three to five years" someone will manage to teleport an atom. After that, teleporting an entire person such as Kirk or Spock would only be a question of repeating that feat with a billion billion billion atoms at once – and creating their copies exactly correctly.

The Australian breakthrough was achieved using a process called "quantum entanglement", which has been the object of repeated experiments around the world for the past few years since its theoretical feasibility was demonstrated nearly a decade ago. Since then about 40 laboratories globally have been experimenting in this area.

In 1998, scientists in California demonstrated that it was possible to "teleport" a single photon, or particle of light. Using a bizarre property of subatomic physics, scientists generate two photons at the same point whose internal properties – called their "spin" – are exactly complementary. This is called "entanglement"; the photons can be sent in different directions from their source, and will keep that spin until they are destroyed by being detected. By finding out the spin of an entangled photon at any point, one automatically knows the spin of the other.

In the Australian experiment, two entangled beams were created. One of the beams was then encoded with radio data and sent over an optical fibre link, while the other was sent to another location in the laboratory. At the far end of the optical fibre, the laser beam was destroyed – and then the other beam was monitored to read the values of its entangled photons. They turned out to contain the data which had been included in the first beam – meaning that the information, and in effect the photons, had been teleported from one place to the other.

The ANU team of scientists from Australia, Germany, France, China and New Zealand is the first to achieve a successful trial with 100 percent reliability.

Teleportation of objects would rely on the fact that if two atoms have the same subatomic properties, such as spin and atomic weight, then they are practically identical. But it would require destroying the object to be teleported at its departure point so that an "identical" one could be created – by giving it the properties of the original – at another location.

That is the unspoken mechanism of the Star Trek transporter – and it's one which might give even the most eager fans pause.

Join our commenting forum

Join thought-provoking conversations, follow other Independent readers and see their replies

Comments

Thank you for registering

Please refresh the page or navigate to another page on the site to be automatically logged inPlease refresh your browser to be logged in