Physicists are transforming quantum chaos into something surprisingly useful

Quantum mechanics controls reality at the smallest levels, but when expanded it is often difficult to assess how and why this field is important in the practical world. That said, physicists will sometimes discover a strangely practical use for spooky quantum phenomena, and when they do, technology is often the biggest beneficiary. Such is the case with a new discovery regarding superradiance, an aspect of quantum mechanics that has traditionally given rise to more headaches than solutions.

Superradiance is a phenomenon in which a group of quantum particles collaborate to produce significantly stronger signals. This remains a serious nuisance for some physicists, because the phenomenon can quickly destabilize quantum systems and, by extension, the operation of key quantum technologies.

However, Austrian and Japanese researchers have developed a new method to harness superradiance to produce powerful, long-lasting microwave signals. The team announced its results today in Natural physics. The team notes that the discovery paves the way for technological advances in medicine, navigation and quantum communication, according to a report. statement.

“This discovery changes the way we view the quantum world,” Kae Nemoto, co-author of the study and a physicist at the Okinawa Institute of Science and Technology (OIST) in Japan, said in the release. “This shift opens up entirely new directions for quantum technologies.”

Questionable Quantum Teamwork

Physicist Robert Dicke proposed the idea of ​​superradiance in 1954. Since then, physicists have identified and even used superradiance for various systems, including semiconductors, experimental x-ray lasersand even to explain the chaos close to rapid radio bursts and black holes.

Superradiance typically occurs when a group of excited atoms become entangled after interacting with a light source. This produces a short but intense burst of light, emitting far more energy from the system than if a single particle bounced off on its own.

Order some chaos

For this experiment, the researchers trapped tiny atomic defects in a microwave cavity. The cavities contained tiny chambers with electronic spins, which served as “miniature magnets” to represent different quantum states. Then, they observed how the system evolved over time, applying the data to extensive computer simulations to better describe the physics at work.

The researchers noticed a strange “train of narrow, long-duration microwave pulses” following a superradiant explosion, which they studied in more detail in their simulations. They found that, surprisingly, “seemingly disordered interactions between spins actually drive the emissions,” Wenzel Kersten, lead author of the study and a physicist at the Vienna University of Technology in Austria, said in the release.

“The system organizes itself, producing a highly coherent microwave signal from the clutter that usually destroys it,” Kersten added.

A reversal of concepts

Because superradiance releases a large amount of energy, scientists have long suspected – and partly confirmed through experiments – that it creates technical challenges for quantum technology.

The new study supplants that view, suggesting instead that with the right approach, the next generation of quantum technologies could benefit from “the very interactions once thought to disrupt quantum behavior,” Nemoto said.

For example, the powerful, self-sustaining microwave signal could help operate ultra-precise clocks, communications links and navigation systems. These signals are also very sensitive to the slightest changes in magnetic or electric fields, a characteristic with potential applications for myriad devices.