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Imagine miniature tornadoes - not in the atmosphere, but in the quantum realm of electrons. These “quantum tornadoes” were theoretically predicted eight years ago, but they have only now been experimentally observed. “Electrons don’t behave just as tiny particles - they also exhibit wave-like properties. And under the right conditions, these quantum waves can swirl into vortices, much like air currents in a tornado,” explained Jakub Schusser, co-author of the study published in the prestigious journal Physical Review X.

The discovery holds promise for emerging fields like spintronics and orbitronics, which explore not just the charge of electrons, but also their intrinsic spin and orbital motion around the atomic nucleus. This could lead to new classes of electronic devices, such as faster, more energy-efficient memory storage—some of these principles are already used in modern hard drives. In the future, orbitronics could pave the way for even more efficient computer chips. Another potential application lies in ultra-sensitive sensors capable of detecting magnetic fields or trace amounts of specific chemical substances. These could be used in medicine (for diagnostics), in industry (for gas leak detection), in environmental monitoring (air quality), or even in smart home systems as pollutant detectors.

The phenomenon was observed in a material called tantalum arsenide (TaAs), a so-called topological semimetal with unusual electronic properties. Unlike conventional semiconductors, in many topological materials, electrons travel primarily along the surface, which is typically more conductive than the bulk. Their movement is remarkably stable and resilient to interference, properties that are particularly valuable for quantum computing. In the future, quantum computers could tackle extremely complex problems in fields like drug development, climate modeling, or advanced materials research, far beyond the capabilities of today's classical machines.

To observe these electron vortices, the researchers used a technique known as angle-resolved photoemission spectroscopy (ARPES). In simple terms, they illuminated the sample with light, which caused electrons to be emitted. They then measured the electrons’ energy and direction of motion, producing a detailed map of the material’s electronic structure, where the vortex patterns first became visible.

“We can think of the electronic world as something like wind,” said Jakub Schusser. “You can’t normally see air currents, but if you scatter flour or release smoke, you suddenly see the swirling motion. That’s essentially what happened here—thanks to advanced techniques, we were able to reveal hidden vortex-like movements of electrons.”

This marks the first-ever experimental observation of a new topological state of matter. “It’s a major discovery for the field of solid-state physics and for orbitronics in particular. Together with research teams from the Universities of Würzburg and Dresden, and other international collaborators, we’ve confirmed long-standing theoretical predictions and opened up new directions for both fundamental physics and future technologies,” said the young physicist from UWB’s NTC.

Interested readers can access the full scientific article.