Researchers have advanced quantum memory technologies to enable long-distance quantum networks, with the University of Strathclyde leading a €2 million EU-funded project.
The development of quantum memories—systems to store quantum information—has taken a significant step forward. These innovations aim to overcome the fragility of quantum signals, which degrade over long distances, and could enable secure communications, quantum internet infrastructure, and new scientific applications.
The AL FreSQO Project and EU Funding
The University of Strathclyde is spearheading the AL FreSQO (Atom-Light Free-Space Quantum Optics networking) project, a €2 million EU-funded initiative to develop quantum ‘memories’ for long-range networks. The three-year effort, involving partners like the Universities of Southampton and Padova, Humboldt University of Berlin, Sabancı University in Istanbul Province and University of Padova spinout ThinkQuantum, focuses on cold-atom quantum memories, free-space optical links, and wavelength conversion to extend quantum communication beyond fibre networks.
Professor Daniel Oi, of Strathclyde’s Department of Physics, the lead coordinator of AL FreSQO, emphasized that quantum signals are fragile and easily lost over long distances
and that the approach uses repeater devices and quantum memories to break long links into shorter ones and reconnect them through entanglement swapping, allowing information to travel much further
.
NASA’s Quantum Memory Breakthrough
NASA’s Glenn Research Center, in collaboration with Infleqtion Inc., has created the agency’s first quantum memory, storing information in a cloud of laser-cooled atoms. Dr. Adam Fallon, a quantum scientist at NASA, noted that if we’re able to put quantum memory into space, then we could use free space transmission and further those distances to spanning the country.
This development is part of NASA’s broader goal to enhance space communications and scientific exploration through quantum technologies.
The memory, developed under the SBIR/STTR program, could eventually enable quantum networks that transmit data securely over vast distances. NASA reported that the technology would allow quantum networks to process information faster and improve the accuracy of space-based sensing compared to traditional systems.
NIST’s Research on Quantum Repeaters
Researchers are testing trapped-ion quantum memories, which could enable entanglement distribution over terrestrial (1000s of km) distances. NIST scientists have achieved lifetimes of longer than 30 minutes for trapped ions, a critical step toward practical quantum repeaters.
Imperial College’s Experiment with Quantum Dots
Researchers at Imperial College London, the University of Southampton, and German institutions achieved a milestone by interfacing a quantum dot light source with a quantum memory. The team stored photons in a rubidium atom cloud and retrieved them using a laser, demonstrating compatibility with existing telecommunications infrastructure.
Dr. Sarah Thomas, a co-author of the study, noted that interfacing two key devices together is a crucial step forward in allowing quantum networking.
The experiment, published in Science Advances, represents the first proof of compatibility between quantum dot photon sources and memory systems at telecommunications wavelengths.
Implications for the Quantum Internet
The advancements across these projects signal progress toward a functional quantum internet, where secure communication, distributed computing, and ultra-precise sensing could become reality. However, challenges remain, including the fragility of quantum states and the need for scalable repeaters.
As these technologies mature, collaborations between academia, industry, and government agencies will be critical. The AL FreSQO project, NASA’s space-ready memory, NIST’s repeater research, and Imperial’s experimental breakthrough all point to a future where quantum networks transcend traditional limitations, reshaping global communication and scientific exploration.
