A powerful quantum internet that's impervious to hacking is a little closer to reality thanks to breakthroughs outlined in two new studies this week.
But an expert warns the super-secure quantum-based network may still be at least a decade away.
Quantum physics and the pursuit of an "unhackable" internet rely on a phenomenon known as entanglement, a process where a pair of particles —photons, for instance — behave like a single particle, even when separated by distance.
While physicists hope to use entanglement to create a sophisticated, more encrypted internet, the challenge to date has been making it work over any significant distance without interference from the Earth's atmosphere.
The move to space
A group of Chinese researchers was the first to launch a quantum satellite last August to help establish "hack-proof" communications between space and the ground, circumventing that interference.
Led by quantum physicist Jian-Wei Pan at the University of Science and Technology of China at Hefei, the group published a report in the journal Science this week showing that it had managed a record-breaking data transmission over a distance of 1,200 kilometres — a dozen times farther than the previous record.
Amr Helmy, a photonics professor in the department of electrical and computer engineering at the University of Toronto, said the achievement of the Chinese group "takes us one step further toward a quantum internet."
"There are many other requirements on which this is predicated that have not been fulfilled yet, but it is indeed an important start," said Helmy in an interview with CBC News.
Those other requirements include issues like storage and processing, hardware powerful enough to make the promise of invincible communications a reality, he said.
Helmy said he believes the quantum internet is still a decade or more away.
You're forgiven if the idea of particles communicating over great distances brings Star Trek-like images to mind.
Nobel-prize winning physicist Albert Einstein referred to this particle entanglement as "spooky action at a distance."
The picture gets even more sci-fi when you consider the second of the two studies out this week from a group led by quantum physicist Christoph Marquardt of the Max Planck Institute for the Science of Light in Erlangen, Germany.
Using the Alphasat I-XL satellite to communicate with the Teide Observatory in Tenerife, Spain, his team found it could measure the quantum properties of laser signals from a satellite 38,600 kilometres away, suggesting an alternate route to a secure quantum communications network.
Their findings, published in the journal Optica this week, were the first to measure the quantum features of lasers from so far away.
The German group suggests their work highlights the feasibility of a quantum communications network that doesn't rely on particle entanglement.