New milestone brings quantum internet closer to reality

Although the quantum internet has so far remained firmly in the theoretical sphere, scientists have made an advance to bring it out of theory and closer to reality through the integration of quantum light sources with quantum memories.

Indeed, a team of Danish and German scientists has launched a massive new project with an aim to create new technology that might just establish the foundation of the future quantum internet, according to the report published by ScienceDaily on June 12.

To this end, they have deployed a rare element called erbium alongside silicon chips (like the ones in our phones) to create special particles of light for ultra-secure communication and powerful computing, using modern-era tools like lasers and nanotech.

Making quantum internet a reality

With this project, called EQUAL (erbium-based silicon quantum light sources), they are trying to turn what was previously impossible into a reality – light that can both travel long distances and remember information – which would enable scalable quantum networks based on the rare-earth element erbium.

According to the project coordinator Søren Stobbe, a professor at the Technical University of Denmark (DTU), which created nanophotonic chips that the team combined with unique technologies in materials, nanoelectromechanics, nanolithography, and quantum systems:

“One of the toughest goals is to integrate quantum light sources with quantum memories. This seemed unrealistic just a few years ago, but now we see a path forward.”

As it happens, erbium has proven to be the only viable option for a quantum light source that both works with quantum memories and is compatible with optical fibers, despite many different types of quantum light sources available today. 

Still, the team had to significantly enhance erbium’s interaction with light, for which it used the new nanophotonic technology developed at DTU. Adding quantum technology, integrated photonics with extremely low power consumption, and new nanofabrication methods into the mix, they managed to get closer to their ultimate goal.

Commenting on the development, Dr. Yonder Berencén, the project’s principal investigator from the Institute of Ion Beam Physics and Materials Research at Helmholtz-Zentrum Dresden-Rossendorf (HZDR), which participates in the project, said:

“We intend to use advanced ion beam techniques to implant erbium atoms into tiny silicon structures and study how using ultra-pure silicon can improve their performance. This research will lay the foundation for building quantum devices that can be integrated into today’s technology.”

Elsewhere, researchers from the Universities of Bristol and Cambridge have earlier successfully completed the United Kingdom’s first long-distance, ultra-secure video call over a quantum communications network, while US researchers have developed an interconnect device towards scalable communication between superconducting quantum processors – or a practical quantum computer.