Figure 1: Figure 1: A scanning electron micrograph of the device that the RIKEN team used to measure the transport properties of their metallic p-wave magnet. © 2026 RIKEN Center for Emergent Matter Science
RIKEN physicists have experimentally demonstrated an exotic form of magnetism in a metal that could be useful for realizing future data-storage devices1.
In fridge magnets and other conventional magnets, the spins of electrons are all aligned in the same direction. In slightly more unusual magnetic materials, neighboring spins point in opposite directions.
But theory has predicted an even more curious form of magnetism in which the spins form a helical pattern in real space, repeating over a distance that is an even multiple of the lattice spacing. This form is known as 'p-wave magnetism', in which the 'p' refers to the symmetry of this spin structure in momentum space, analogous to p orbitals of electrons in atoms.
Far more than a physical curiosity, a p-wave magnet could have applications in future spintronic memory devices.
A theoretical paper published in 2024 proposed a method for producing a p-wave magnet. But interestingly, the RIKEN team had already created a p-wave magnet in the lab before that-they just weren't sure what it was until they saw the theoretical paper.
"The signal we'd seen was very striking, but we were a bit ahead of our time with the experiment," recalls Max Hirschberger of the RIKEN Center for Emergent Matter Science (CEMS). "We needed guidance from the theoretical group to really understand what we had seen."
Hirschberger, Rinsuke Yamada, also of CEMS, and their co-workers created their p-wave magnet in a metal.
The team narrowly missed being the first to report a p-wave magnet. They were pipped at the post by a team in the US who created a p-wave magnet in a non-metallic system. "They beat us by about three months," notes Hirschberger. "It was a kind of neck-to-neck race."
But Yamada's team was the first to demonstrate a p-wave magnet in a metal, which should open up further applications. The closeness of the two publications is an indication of how fast the field is currently moving, Hirschberger says, with a lot of interest in developing novel magnets.
Fine-tuning the composition of the metal proved critical for realizing the p-wave magnet. "We found that a tiny change in the composition of the metal resulted in a huge effect," says Yamada. "So meticulous experimental control was a key in this experiment."
In the long term, understanding and controlling a p-wave magnet could lead to new spintronics technologies that enable low-power, high-performance electronic devices. The team now intends to explore spintronics applications and to contribute to the development of new materials and experimental methods.
Max Hirschberger (second row; third from left) and Rinsuke Yamada (third row; first on right) and co-workers have found a metallic p-wave magnet that has a commensurate spin helix. © 2026 RIKEN
