A photon has teleported 500km into space, making history in the process

12 Jul 2017

Image: Mikhail Varentsov/Shutterstock

While far removed from the likes of what we’ve seen in Star Trek, a photon being teleported 500km into space is a big deal.

Quantum science has been given a major boost with the news that a Chinese spacecraft and laboratory, named after one of the country’s philosophers, has achieved photon ‘teleportation’.

According to MIT Technology Review, the Micius spacecraft launched from the Gobi Desert last year has now achieved the first satellite-to-ground quantum network and, in the process, destroyed the record for quantum entanglement distance at 500km.

The process of entanglement allows for two particles to react with one another, despite having no physical connection.

In the world of quantum – and particularly quantum optics – it has become a focus to create greater and greater distances between these two particles, resulting in this latest achievement.

By comparison, a research team announced towards the end of last year that it had achieved quantum entanglement of just 6km.

While it might not look like the process seen in science fiction, this teleportation of a photon involves ‘downloading’ the information of the original photon and transmitting it to another location through entanglement.

The second photon on the other end of the transmission then, in effect, takes on the identity of the first.

‘Essential step toward global-scale quantum internet’

Despite many examples being conducted on Earth, this latest breakthrough marks a major step forward in all things quantum.

“Long-distance teleportation has been recognised as a fundamental element in protocols such as large-scale quantum networks and distributed quantum computation,” the Chinese team said.

“Previous teleportation experiments between distant locations were limited to a distance on the order of 100km, due to photon loss in optical fibres or terrestrial free-space channels.”

To overcome these difficulties, the team placed a ground station at an altitude of 4km in Tibet where Micius, at its closest point, is 500km above.

For just over a month, millions of photons were beamed up into space to be captured by the spacecraft, 911 of which were successfully teleported, marking the first time that this has happened outside of Earth.

For the research team, it represents the first foray into a whole new field of communication. “This work establishes the first ground-to-satellite uplink for faithful and ultra-long-distance quantum teleportation – an essential step toward global-scale quantum internet.”

Colm Gorey was a senior journalist with Silicon Republic