Altermagnetism, a magnetic state with no net magnetisation but spin-split bands, has mostly been studied in materials with three- or two-dimensional exchange interactions. Focusing on the known van der Waals magnet AgCrP₂S₆, researchers show that antiferromagnetic chains embedded in a 2D lattice offer a general route to altermagnetism.

First-principles calculations and spin-space-group analysis show that breaking out-of-plane symmetry creates d-wave spin splitting: an out-of-plane electric field induces a splitting that grows linearly with the field and reverses with its direction. Janus substitution and interfacing with ferroelectric CuInP₂S₆ offer further control. The work is a collaboration between the University of Valencia and QMAT's Correlated Quantum Materials group at Aalto University (Cuiju Yu, Jose Lado and Adolfo Fumega).

The preprint has not yet been peer reviewed.

Figure: Ruiz et al., arXiv:2607.16856 (2026), CC BY 4.0