01 Oct Conventional and quantum internet in the same fiber optic network
Researchers at Leibniz Universität Hannover are sending entangled photons and laser pulses of the same wavelength over a single optical fiber for the first time. This means that the next generation of telecommunications technology, the so-called quantum internet, could also be routed via existing optical fibers. “To make the quantum internet a reality, we need to transmit entangled photons over fiber optic networks,” says Professor Michael Kues, head of the Institute of Photonics and board member of the PhoenixD Cluster of Excellence at Leibniz Universität Hannover. In their experiment, the researchers were able to prove that the entanglement of the photons is maintained even when they are sent together with a laser pulse. According to the researchers, this effect could make it possible to combine conventional internet with the quantum internet. Until now, only one of the two transmission methods per wavelength could be implemented in an optical fiber. “The entangled photons block a data channel in the optical fiber, which can therefore no longer be used for conventional data transmission,” says Jan Heine, a doctoral student in Kues’ group.
The four researchers involved in the project in the quantum optics laboratory: (from left) Jan Heine, Philip Rübeling, Michael Kues and Robert Johanning. Picture: Institute of Photonics
With the concept demonstrated for the first time in the experiment, the photons can now be sent in the same channel as the laser light. This means that all channels can still be used for conventional data transmission. “Our experiment shows how the practical implementation of hybrid networks can succeed,” says Kues.
Original publication:
[Philip Rübeling, Jan Heine, Robert Johanning and Michael Kues, Quantum and coherent signal transmission on a single frequency channel via the electro-optic serrodyne technique, Science Advances (2024), https://doi.org/10.1126/sciadv.adn8907]
Source: www.uni-hannover.de
Image: Institute of Photonics
