Scientists Just Found a Third Type of Magnetism, And It Could Change Electronics

For more than a century, physicists largely treated magnetism as a two-option system. Materials either had their tiny magnetic moments lined up like a conventional magnet, or those moments pointed in opposite directions and cancelled each other out. Then one stubborn piece of metal began behaving as though the rules had left something important out. Ruthenium dioxide kept producing an electrical effect that should have been associated with ferromagnets, even though its atomic spins appeared to cancel perfectly. The strange result sent researchers back to the drawing board and eventually helped reveal an entirely new class of magnetic material.

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That class is now known as an altermagnet, and scientists believe it could eventually have major consequences for electronics. Unlike a conventional magnet, an altermagnet can have no overall magnetic field while still producing electronic behavior associated with ferromagnetism. Researchers have already demonstrated altermagnetic order in manganese telluride and identified hundreds of potential materials that could belong to the family. The technology is still firmly in the research stage, but the physics could eventually allow magnetic information to be packed more tightly, switched much faster and potentially operated with less energy.

The Mystery Started With A Metal That Should Not Behave This Way

The story goes back to 2018, when theorist Libor Šmejkal was working in Jairo Sinova’s group at Johannes Gutenberg University in Mainz. The researchers were studying ruthenium dioxide, a metal that repeatedly produced an anomalous Hall effect, meaning that an electrical current could be pushed sideways through the material in a way normally associated with ferromagnetic materials. That was a serious problem for the standard explanation because ruthenium dioxide was not behaving like a conventional ferromagnet. Its atomic spins pointed in opposite directions and appeared to cancel each other, leaving researchers with no obvious reason for the material to produce the effect they were measuring.

Šmejkal eventually took the problem to a supercomputer, hoping a detailed calculation could explain what was happening inside the crystal. Instead of finding a small correction to an existing theory, the calculations pointed toward something much more interesting. The crucial feature was not simply the direction of the atomic spins. It was the relationship between those spins and the crystal structure surrounding them. The discovery suggested that magnetic materials could possess a combination of properties that physicists had previously treated as belonging to separate categories.

The result changed the question being asked. Researchers were no longer simply trying to understand why one unusual metal was misbehaving. They were asking whether an entire class of materials had gone unnoticed because scientists had been searching for magnetism using an incomplete set of rules. By 2022, Šmejkal, Sinova and Tomas Jungwirth had developed a systematic symmetry classification and identified hundreds of potential materials. What had started as an awkward measurement in one compound had turned into a new area of condensed-matter physics.

The Missing Piece Was Hidden Inside The Crystal

The key to the mystery was hiding in the architecture of the material itself. In ruthenium dioxide, each metal atom sits inside a cage made from oxygen atoms, and that cage changes the shape of the electron cloud surrounding the metal. Neighboring cages are rotated by 90 degrees relative to one another, creating a pattern that remains important even though the magnetic moments themselves point in opposite directions. The spins cancel overall, but the surrounding electronic structure does not simply disappear with them.

That difference allows the material to break time-reversal symmetry in a way that produces unusual electronic behavior. In ordinary terms, the magnetic moments can balance one another while the crystal still retains information about how those moments are arranged. That is what gives altermagnets their unusual position between the two familiar categories. The material does not need to behave like a refrigerator magnet to possess an electronic structure that can produce effects associated with much more familiar magnetic materials.

Šmejkal later described the discovery as a systematic way of identifying materials with these properties. The theoretical work with Sinova and Jungwirth showed that the phenomenon was not limited to ruthenium dioxide and could instead exist across a broad family of compounds. That realization was crucial because a new physical phase becomes far more interesting when researchers can search for many examples rather than trying to explain one isolated anomaly.

Altermagnets Sit Between Two Familiar Types

A conventional ferromagnet works because many of its magnetic moments point in the same direction, producing a net magnetic field outside the material. That is the basic reason a familiar fridge magnet can attract certain metals or hold a piece of paper against a refrigerator door. Antiferromagnets behave differently because their magnetic moments alternate between opposite directions, causing the overall magnetisation to cancel. For decades, those two arrangements represented two very different ways for magnetically ordered materials to behave.

Altermagnets add a third possibility. Their magnetic moments can point antiparallel to neighboring moments, much like an antiferromagnet, while the crystal environments around those moments are rotated relative to one another. That structural difference changes the electronic behavior without creating a large net magnetic field. Peter Wadley, a physicist at the University of Nottingham who later helped experimentally investigate the phenomenon, described it this way: “Altermagnets consist of magnetic moments that point antiparallel to their neighbours. However, each part of the crystal hosting these tiny moments is rotated with respect to its neighbours. This is like antiferromagnetism with a twist!”

That twist is what makes the materials potentially useful. A conventional ferromagnet produces a magnetic field that can interfere with nearby components, while an antiferromagnet avoids that problem but lacks some of the electronic properties researchers want for certain technologies. Altermagnets could potentially combine the advantages of both arrangements. They have no overall magnetisation, yet they can possess spin-split electronic bands that make them interesting candidates for future spin-based electronics.

Scientists Finally Managed To See The New Magnetic Order

Predicting a new phase of matter on a computer is one thing. Producing a material and directly identifying the predicted order is considerably harder. Researchers led by Wadley tackled that challenge using 30-nanometre films of manganese telluride at the MAX IV synchrotron in Lund, Sweden. They directed polarised X-rays at the films and studied the electrons released from their surfaces. The resulting patterns carried information about the magnetic structure inside the material, allowing the team to look for signatures that would distinguish altermagnetic order from more familiar forms of magnetism.

The experiments revealed structures ranging from roughly 100-nanometre vortices and domain walls to individual domains several micrometres across. The researchers also demonstrated that these patterns could be manipulated under controlled conditions. They heated the manganese telluride above its approximately 310 K transition temperature and then cooled it toward 100 K while applying a 0.4 tesla magnetic field. The ability to observe and manipulate these structures gave experimental weight to a concept that had previously existed largely through theory and calculations.

For the researchers involved, the observations represented a major step from mathematical prediction toward physical demonstration. Alfred Dal Din, a PhD student on the team, described the experience as “an immensely rewarding and challenging privilege.” The images were not simply attractive maps of a microscopic material. They provided researchers with a way to study the new magnetic order directly and begin testing whether its unusual properties could eventually be controlled in ways useful for technology.

The Technology Could Be Much Faster

The potential engineering advantage comes from the way altermagnets handle magnetic information. Because they can have no net magnetic field, neighboring magnetic elements may be able to sit closer together without interfering with one another in the same way that conventional magnetic components can. That could become valuable as engineers try to squeeze more information into smaller spaces. If magnetic states can also be switched quickly, altermagnetic materials could become candidates for future forms of memory and other electronic components.

Researchers at Nottingham have suggested that the underlying physics could eventually support operating speeds up to 1,000 times those of some current microelectronic components and digital memory, while using less energy. That number needs an important qualification: it is a projection based on the properties of the material and the physics of the system, rather than a result from a commercial altermagnetic chip. No consumer device is currently delivering that performance using the technology.

The researchers are therefore treating the work as a possible path rather than a finished product. Oliver Amin, the senior research fellow who led the experimental work, said the experiments “provided a bridge between theoretical concepts and real-life realisation” and could help illuminate a path toward practical altermagnetic materials. That distinction matters because many promising materials have taken years or decades to move from laboratory demonstrations into reliable technologies.

The Promise Comes With Some Serious Obstacles

The biggest challenge is control. The experiments have shown that altermagnetic domains can be observed and manipulated, but controlling them efficiently inside a working electronic device is much more complicated. The Nottingham researchers used field cooling as part of their experimental method, while practical electronics would ideally control magnetic states directly using electrical currents. That would make the technology far easier to integrate into conventional circuits and memory systems.

Researchers have reported electrical switching in altermagnetic heterostructures during 2026, giving the field another important avenue to investigate. Even so, reliably switching an entire device into the desired magnetic state remains difficult. Materials can contain multiple domains, and getting those regions to respond predictably is essential if an altermagnet is ever going to store digital information reliably.

There is also the basic problem of identifying which materials genuinely qualify as altermagnets. The discovery has created hundreds of candidates, but theoretical predictions still need to be matched against careful experiments. Researchers need to understand how crystal structure, defects, strain and interfaces affect the magnetic behavior before they can determine which materials are practical candidates for future electronics.

Ruthenium Dioxide May Not Be The Altermagnet Scientists Expected

The material that started the entire investigation has created another twist in the story. High-quality bulk ruthenium dioxide crystals have been examined using neutron diffraction, muon spin rotation and photoemission techniques, yet those studies have not found the long-range magnetic order that would be expected from a straightforward altermagnetic interpretation. At the same time, thin films of ruthenium dioxide have continued to produce transport signatures that researchers associate with the phenomenon.

Scientists have several possible explanations for the discrepancy. Strain, vacancies, disorder and interfaces can all change the behavior of a material, particularly when researchers are working with extremely thin films. Ruthenium dioxide could also sit close to a boundary between different physical states, meaning that small changes in its environment might have an outsized effect on the measurements.

That leaves ruthenium dioxide in an unusual position. It may have been the material that revealed the clue without being the definitive example of the new magnetic phase. The broader discovery does not depend on solving that particular mystery because manganese telluride has provided experimental evidence for altermagnetic order, while researchers continue searching through hundreds of other possible materials.

Three Scientists Have Now Received Recognition For The Discovery

The European Physical Society’s Condensed Matter Division awarded its 2026 Europhysics Prize to Šmejkal, Sinova and Jungwirth for the discovery of altermagnetism. The ceremony was scheduled for September 22, 2026, in Graz, recognizing the theoretical and experimental work that transformed an unexpected material behavior into a new area of research.

The recognition also reflects how quickly the field has expanded. Šmejkal’s original calculations helped explain the strange behavior observed in ruthenium dioxide, while subsequent theoretical work identified a broader family of materials. Experiments then moved the concept beyond computer models by demonstrating altermagnetic order in manganese telluride.

Sinova described the significance of the discovery in unusually broad terms: “Discovering that an entirely new magnetic phase had remained hidden for more than 100 years demonstrates that even the most mature scientific fields can still hold fundamental surprises.” The statement captures the central surprise behind the discovery. Scientists were not looking at an unknown force or an exotic substance from another world. They were looking at familiar materials through a set of categories that turned out to be incomplete.

Why Researchers Think Altermagnets Could Matter

The possible applications extend beyond simply adding another category to physics textbooks. If researchers learn how to manufacture and control these materials reliably, their unusual combination of properties could make them useful for future electronic systems. Several possibilities are already being investigated:

  • Denser memory: The lack of a large external magnetic field could reduce interference between neighboring magnetic elements and potentially allow components to be placed closer together.
  • Faster switching: The electronic structure of altermagnets could support very rapid manipulation of magnetic information.
  • Lower energy use: Faster and more efficient switching could eventually reduce the energy required by certain electronic components.
  • New material choices: Hundreds of candidate compounds give researchers many different structures to investigate rather than relying on one material.
  • Less reliance on heavy elements: Some altermagnetic materials could eventually provide alternatives to components that depend on rare or toxic elements.

None of those applications has reached everyday consumer electronics yet. The research is still focused on understanding the materials, controlling their domains and developing reliable methods for switching them. The gap between a laboratory demonstration and a commercial technology remains significant, but the basic physical discovery gives researchers a new direction to pursue.

A Third Box Was Hiding In Plain Sight

For roughly 100 years, the standard categories of magnetism gave physicists two familiar choices. Ferromagnets could produce a net magnetic field, while antiferromagnets could cancel their magnetic moments. Altermagnets showed that those properties do not necessarily have to come as a package, allowing magnetic moments to cancel while the material retains an electronic structure capable of producing effects associated with ferromagnets.

That is what makes the discovery so intriguing. The third category was not created by forcing an existing material into an artificial experiment. The clues were already present in materials scientists had been studying for years. The breakthrough came when researchers realized that the crystal structure itself could change what magnetism was capable of doing.

The next challenge is turning that realization into something engineers can control. If they succeed, a discovery that began with one puzzling metal could eventually reshape how magnetic information is stored and manipulated.

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Michelle

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