For the first time, a team led by Innsbruck physicist Ben Lanyon has sent a light particle entangled with matter over 50 km of optical fiber. This paves the way for the practical use of quantum networks and sets a milestone for a future quantum internet.
The quantum internet promises absolutely tap-proof communication and powerful distributed sensor networks for new science and technology. However, because quantum information cannot be copied, it is not possible to send this information over a classical network. Quantum information must be transmitted by quantum particles, and special interfaces are required for this. The Innsbruck-based experimental physicist Ben Lanyon, who was awarded the Austrian START Prize in 2015 for his research, is researching these important intersections of a future quantum Internet. Now his team at the Department of Experimental Physics at the University of Innsbruck and at the Institute of Quantum Optics and Quantum Information of the Austrian Academy of Sciences has achieved a record for the transfer of quantum entanglement between matter and light. For the first time, a distance of 50 kilometers was covered using fiber optic cables. “This is two orders of magnitude further than was previously possible and is a practical distance to start building inter-city quantum networks,” says Ben Lanyon.
Converted photon for transmission
Lanyon’s team started the experiment with a calcium atom trapped in an ion trap. Using laser beams, the researchers write a quantum state onto the ion and simultaneously excite it to emit a photon in which quantum information is stored. As a result, the quantum states of the atom and the light particle are entangled. But the challenge is to transmit the photon over fiber optic cables. “The photon emitted by the calcium ion has a wavelength of 854 nanometers and is quickly absorbed by the optical fiber”, says Ben Lanyon. His team therefore initially sends the light particle through a nonlinear crystal illuminated by a strong laser. Thereby the photon wavelength is converted to the optimal value for long-distance travel: the current telecommunications standard wavelength of 1550 nanometers. The researchers from Innsbruck then send this photon through a 50-kilometer-long optical fiber line. Their measurements show that atom and light particle are still entangled even after the wavelength conversion and this long journey.
Even greater distances in sight
As a next step, Lanyon and his team show that their methods would enable entanglement to be generated between ions 100 kilometers apart and more. Two nodes send each an entangled photon over a distance of 50 kilometers to an intersection where the light particles are measured in such a way that they lose their entanglement with the ions, which in turn would entangle them. With 100-kilometer node spacing now a possibility, one could therefore envisage building the world’s first intercity light-matter quantum network in the coming years: only a handful of trapped ion-systems would be required on the way to establish a quantum internet between Innsbruck and Vienna, for example.
Learn more: Entanglement sent over 50 km of optical fiber
The Latest on: Quantum internet
via Google News
The Latest on: Quantum internet
- Physicists irreversibly split photons by freezing them in Bose-Einstein condensate on November 14, 2019 at 1:45 pm
"Perhaps quantum computers might one day use this method to communicate with each other and form a kind of quantum Internet," says Weitz with a view towards the future. University of Bonn. (2019, ...
- Physicists irreversibly split photons by freezing them in a Bose-Einstein condensate on November 14, 2019 at 11:02 am
"Perhaps quantum computers might one day use this method to communicate with each other and form a kind of quantum Internet," says Weitz with a view towards the future.
- Don’t Rush Quantum-Proof Encryption, Warns NSA Research Director on November 11, 2019 at 11:04 am
Quantum computers could crack the codes that secure the world’s digital information ... A company looking to encrypt a device on the internet of things may want to prioritize speed, and thus opt for ...
- New quantum data protocol takes big steps towards a 'Quantum Internet' on November 11, 2019 at 12:14 am
Everyday efforts are being made towards the creation of 'quantum internet,' and now a new network protocol has been developed that bring us even closer to its fruition. UAB researchers have managed to ...
- A Glimpse Into Honeywell’s Quantum Play Through Microsoft’s Azure Ignite Announcement on November 9, 2019 at 4:04 pm
Azure Quantum will provide internet cloud access to Honeywell’s quantum computer along with those of IonQ and QCI. The service also includes access to Microsoft's open-source Quantum Development Kit ...
- A new quantum data classification protocol brings us nearer to a future 'quantum internet' on November 8, 2019 at 9:24 am
thus setting the bases for a future "quantum internet." With the design of these quantum information networks come new theoretical challenges, given that it is necessary to establish optimised ...
- What happens at a quantum internet hackathon? on November 8, 2019 at 2:22 am
After researchers in Dublin joined forces with teams in five other cities for a pan-European Quantum Internet Hackathon, Dr Harun Šiljak describes the experience. You’re going to hear a lot more about ...
- Quantum Computing Won’t Kill The Blockchain on November 7, 2019 at 1:46 am
we will not have to worry about quantum supremacy any time soon. (Xinxin Fan is head of Cryptography of IoTeX, a technology company that uses blockchain, secure hardware, and trusted computing to ...
- The promise and peril of post quantum computing on November 6, 2019 at 10:38 pm
That means post quantum crypto in conjunction with RSA or ECC. This is quite an interesting approach because, as many security professionals know, and obviously Internet users might know, security and ...
- Microsoft Is Taking Quantum Computers to the Cloud on November 4, 2019 at 1:00 am
The company’s partners will run their quantum computers in their own facilities, but link them into Microsoft’s cloud over the internet. Microsoft has a long-running quantum research program of its ...
via Bing News