Researchers have experimentally confirmed altermagnetism, a third magnetic phase combining properties of ferromagnets and antiferromagnets, with major implications for future computing technologies.
By Adam Makins·
For nearly 90 years, physicists have operated with a simple division: ferromagnets and antiferromagnets. These two categories seemed to cover everything the magnetic world had to offer. But a groundbreaking study published in Science has just upended that assumption, revealing a third type of magnetism that could fundamentally reshape how we build computers and data storage systems.
Researchers at SLAC National Accelerator Laboratory have provided the first definitive experimental proof of altermagnetism, a distinct magnetic phase that researchers have theorized about for only a few years. The discovery hinges on identifying a subtle but crucial property called chirality in manganese telluride, a material long thought to be a conventional antiferromagnet.
To understand why this matters, we need to talk about electron spin. At the atomic level, magnetism arises from the quantum property of electrons called spin, which behaves as though electrons possess their own angular momentum. Scientists describe two possible orientations: up and down.
In ferromagnets, all spins align the same direction, creating the familiar magnetic fields we experience with everyday magnets. In antiferromagnets, discovered in 1933, neighboring spins point in opposite directions, canceling each other out and producing no detectable external magnetic field.
For decades, this binary framework worked fine. But recent experiments started showing materials with bizarre hybrid properties. They displayed alternating spins like antiferromagnets, yet somehow generated useful spin currents, a trait previously associated only with ferromagnets. Something didn’t fit.
That something is altermagnetism. These materials have alternating spin patterns, but here’s the kicker: the crystal structures surrounding oppositely aligned spins are rotated relative to one another. This subtle rotation breaks a symmetry that exists in conventional antiferromagnets, fundamentally changing how electrons behave and allowing seemingly incompatible properties to coexist.
Even as evidence accumulated, researchers needed one decisive proof that altermagnetism was genuinely real. That proof arrived through detecting chirality, a property sometimes called handedness. Think of it like your left and right hands: they’re mirror images, but a left hand doesn’t fit in a right-handed glove.
Materials can possess this same handedness in their electronic and magnetic structure. Detecting that chiral signature in manganese telluride would definitively prove it wasn’t a conventional antiferromagnet.
The team conducted experiments at the European Synchrotron Radiation Facility using circularly polarized X-rays that rotate either left-handed or right-handed as they travel. Chiral materials scatter these two forms of light differently, while non-chiral materials scatter them identically.
The results were unambiguous. Manganese telluride scattered left-handed and right-handed polarized X-rays in distinctly different ways, producing exactly the chiral signature predicted by altermagnetic theory. The team repeated the measurements in early 2025, successfully reproducing the findings and cementing the evidence.
The implications reach far beyond academic physics. Altermagnetism could transform spintronics, a rapidly growing field that harnesses electron spin to build faster, more efficient electronics. Traditional electronics rely primarily on electron charge to store and process information. Adding spin into the mix creates new possibilities.
Here’s the problem with current approaches: ferromagnets are too vulnerable to external magnetic interference, while antiferromagnets are so magnetically invisible that reading data from them is extremely difficult. Altermagnets solve both issues simultaneously. They possess zero net magnetization, making them stable against unwanted magnetic fields, yet they still generate spin-polarized currents that can retrieve information efficiently.
“Altermagnets combine the best of both,” explained lead researcher Daniel Jost. “They’re stable but still have the capability to generate spin-polarized currents needed to easily extract information.”
This combination could enable revolutionary advances in quantum computing, computer memory systems, and energy-efficient data centers. Devices built with altermagnetic materials could operate faster, consume far less electricity, and resist interference more effectively than today’s technology.
The research community now faces an exciting challenge: learning to control altermagnetic states using external influences like light and electricity. Once scientists master this control, practical spintronic devices could finally become reality, transforming industries that depend on processing massive amounts of information.
While significant development remains before magnetism-based computing becomes mainstream, this confirmation provides the experimental foundation for a new generation of technological possibilities.
Source: Materials provided by SLAC. Original written by Erin Woodward.
If a material can bridge the gap between stability and usability, what other scientific dichotomies might actually be hiding a hidden third way?
