HWBRIEF
University of Central Florida physicists see opposite spins in a layered cobalt crystal, evidence altermagnetism is a third class of magnetism that could let future chips use spin, not just charge.
A University of Central Florida team led by physicist Madhab Neupane has spotted a textbook spin-split signature in a layered crystal called Co1/4TaSe2, the latest experimental evidence that altermagnetism is a real third class of magnetism, distinct from the ferromagnet of fridge magnets and the silent antiferromagnet.
Altermagnetism combines the spin-polarized bands of a ferromagnet, which can carry information, with the stray-field-free character of an antiferromagnet, which stays invisible to neighboring circuits. The new Nature Communications paper shows both in a cobalt-intercalated transition-metal dichalcogenide probed by spin-resolved ARPES.
The result is a material-level observation, not a device. The crystal is layered and tunable, which turns it into a research platform for follow-up experiments.
The stake is long-term. If future chips use electron spin alongside charge, ferromagnets leak stray fields and antiferromagnets are hard to read. An altermagnet would offer both. The UCF press release describes the result as a path to "faster, more energy-efficient electronic devices," language the underlying paper does not claim.
Funding came from the U.S. Department of Energy, Office of Science, under Award DE-SC0024304. What remains open: whether any altermagnet can be grown into functional thin films at device scale and integrated with silicon.