Physicists at Leibniz University Hannover’s Institute of Photonics have made a groundbreaking discovery.
They’ve developed a new way to send special light particles called entangled photons over optical fibers, which could pave the way for the next generation of internet technology—the quantum internet.
This new type of internet promises super-secure encryption that even future quantum computers won’t be able to break, ensuring the safety of critical infrastructure.
Professor Dr. Michael Kues, head of the Institute of Photonics, explains, “To make the quantum internet a reality, we need to send entangled photons through fiber optic networks.
We also want to keep using these fibers for our current internet. Our research is a big step towards combining both.”
The team of four researchers showed that entangled photons stay connected even when sent along with a laser pulse through the same optical fiber.
Their findings were published in the journal Science Advances.
Philip Rübeling, a doctoral student working on the quantum internet, explains further, “We can change the color of a laser pulse with a fast electrical signal to match the color of the entangled photons.
This allows us to send both the laser pulse and the entangled photons together in the same fiber and then separate them again.”
This new technique means that the same fiber optic cables can be used for both the conventional internet and the quantum internet. Before this discovery, using both methods together wasn’t possible because entangled photons would block a channel in the fiber, making it unusable for regular data transmission.
Jan Heine, another doctoral student in Kues’ group, adds, “The entangled photons would block a data channel, preventing its use for conventional data transmission.”
With their new concept, the team demonstrated that photons can now travel in the same color channel as the laser light, meaning all color channels can still be used for regular internet traffic. Professor Kues concludes, “Our experiment shows how we can practically implement hybrid networks that combine today’s internet with the quantum internet.”
This breakthrough brings us closer to a future where our current internet and the ultra-secure quantum internet work together, making our digital world safer and more efficient.
