Spreading the Altermagnetic Love
Discovered in the past few years, altermagnets combine a particular type of momentum- and spin-dependent energy of the mobile electrons with zero net magnetization—a desirable combination for a range of future electronic applications. Now Tong Zhou of the Eastern Institute of Technology, Ningbo, China, and his colleagues have shown theoretically that altermagnetism can be acquired by a nonmagnetic material immediately adjacent to an altermagnet [1]. The effect could potentially make altermagnetic properties available in more materials.
Proximity effects allow a material to gain properties such as magnetism or superconductivity from an adjacent material, but it was not clear whether such an effect would work for altermagnetism. To find out, Zhou and his colleagues modeled a two-layer structure with the altermagnet V2Se2O as the bottom layer and the semiconductor PbO as the top layer.
Their calculations and simulations revealed two key signatures of altermagnetism in the PbO, both appearing with the expected symmetry. One is a band structure in which spin-up and spin-down electrons have different energies that vary in a periodic pattern. The other is a pattern of electron spins—a spin texture—that sums to zero net magnetization in the material. To demonstrate the generality of the effect, Zhou and his colleagues studied several other combinations of altermagnetic and nonmagnetic layers. They found that other useful properties, such as topological superconductivity, can be generated in the nonmagnetic material as a result of the altermagnetic proximity effect.
The team also showed that the strength of the effect depends sensitively on the distance between the layers, suggesting that the effect could be adjustable in the lab by changing parameters such as layer spacing or pressure. Next the team plans to determine other potential “control knobs.”
–David Ehrenstein
David Ehrenstein is a Senior Editor for Physics Magazine.
References
- Z. Zhu et al., “Altermagnetic proximity effect,” Phys. Rev. Lett. 136, 186702 (2026).