Superradiance discovery "changes how we think about the quantum world", scientists claim
"The very interactions once thought to disrupt quantum behavior can instead be harnessed to create it, opening entirely new directions..."
Typically, a phenomenon called superradiance is bad news for quantum because it makes systems lose their energy too quickly.
Now scientists from universities in Austria and Japan have found that superradiant effects can actually produce "self-sustained, long-lived microwave signals with exciting potential for future quantum devices."
Robert H. Dicke first proposed the concept of superradiance in 1954 after he discovered that closely packed atoms could emit light collectively, releasing their energy in a single, amplified flash.”
In a release announcing their discovery, researchers from TU Wien (Vienna University of Technology) and the Okinawa Institute of Science and Technology (OIST) said "teamwork" between quantum particles lets them produce "far stronger" signals than they would be able to achieve independently.
“What’s remarkable is that the seemingly messy interactions between spins actually fuel the emission,” explains Dr Wenzel Kersten, first author of the study. “The system organizes itself, producing an extremely coherent microwave signal from the very disorder that usually destroys it.”
A quantum leap for superradiant research
They were able to demonstrate self-induced superradiant masing, spontaneously generating "long-lived" bursts of microwave emission generated without external
This discovery uncovered a new way of generating stable and precise microwave signals, setting a foundation for advances in a variety of areas ranging from navigation to quantum communication.
“This discovery changes how we think about the quantum world,” says Professor Kae Nemoto, Center Director of the OIST Center for Quantum Technologies. “We’ve shown that the very interactions once thought to disrupt quantum behavior can instead be harnessed to create it. That shift opens entirely new directions for quantum technologies.”
To investigate how spin systems behave collectively, the researchers coupled a dense ensemble of nitrogen-vacancy (NV) centres in diamond to a microwave cavity. Each NV centre contains electron spins that can be switched between quantum states, effectively acting as microscopic magnets.
“We observed the expected initial superradiant burst—but then a surprising train of narrow, long-lived microwave pulses appeared,” explains Professor William Munro, co-author of the study and head of OIST’s Quantum Engineering and Design Unit.
The team identified the source of this pulsing: self-induced spin interactions that dynamically repopulate energy levels, sustaining emission without external pumping.
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“Essentially, the system drives itself,” Professor Munro added. “These spin–spin interactions continually trigger new transitions, revealing a fundamentally new mode of collective quantum behavior.”
Beyond revealing new quantum physics, the results also point to practical uses. For example, stable, self-sustaining microwave emission could underpin ultra-precise clocks, communication links, and navigation systems which are technologies at the heart of modern life, from GPS and telecommunications to radar and satellite networks.
“The principles we observe here could also enhance quantum sensors capable of detecting minute changes in magnetic or electric fields,” says Professor Jörg Schmiedmayer of the Vienna Center for Quantum Science and Technology, TU Wien.
“Such advances could benefit medical imaging, materials science, and environmental monitoring. More broadly, this work shows how deep insights into quantum behavior can translate into new tools and technologies to shape the next generation of scientific and industrial innovation.”
