Researchers teleport light particle 6km, could lead to quantum internet

23 Sep 2016

Abstract colour wormhole tunnel. Image: u3d/Shutterstock

A team of researchers might just have taken the first step towards a quantum internet, after they successfully teleported a particle of light 6km away over a straight line distance.

While our first thought of being able to teleport something makes us think of the Transporter machine in Star Trek, researchers working in advanced photonics have found a way to teleport light, rather than organic matter.

As part of a collaboration between the University of Calgary in Canada and researchers in the US, a team of researchers have successfully demonstrated the teleportation of a particle of light – referred to as a photon – across a distance of 6km.

Spooky science

Having been teleported via a fibre optic cable across the city of Calgary, this teleportation has set a new record for transferring a quantum state by teleportation. More importantly, it could usher in a new internet age.

The science behind this event relates to what is often referred to as the ‘spooky action at a distance’, or the entanglement property of quantum mechanics.

Lead researcher on the project, Prof Wolfgang Tittel, explained that the entanglement process means that the two photons form an entangled pair with linked properties, regardless of how far apart they are.

When one of the photons was sent over to Calgary’s city hall, it remained entangled with the photon that stayed at the University of Calgary.

Transported in one trillionth of a second

Confusingly, the photon that was teleported to the university was also generated in a third location in Calgary, before being teleported to city hall, thereby meeting the photon that was part of the entangled pair.

To make matters even more difficult for the researchers, the efficiency of the teleportation varied greatly depending on the outside temperature at any given time of day.

“The challenge was to keep the photons’ arrival time synchronised to within 10 pico-seconds,” Tittel said. “That is one trillionth, or one millionth of one millionth of a second.”

While this technology is still limited to testing in temperatures of absolute zero, it is hoped it will one day lead to a future of quantum computing and more specifically, quantum internet.

Secure quantum internet

In the city of Calgary, officials have discussed the rolling out of ‘dark fibre’ that prevents interference from any outside source to ensure the fastest speeds possible.

“By opening the city’s dark fibre infrastructure to the private and public sector, non-profit companies, and academia, we help enable the development of projects like quantum encryption and create opportunities for further research, innovation and economic growth in Calgary,” said Tyler Andruschak, project manager with Innovation and Collaboration at the City of Calgary.

Tittel also added that a quantum internet would ensure a secure communication line that could prevent eavesdropping.

The team’s research has now been published in Nature Photonics.

Colm Gorey was a senior journalist with Silicon Republic