2026, Altermagnetism in Twisted van der Waals Homostructures, Nature Physics.

2026, Altermagnetism in Twisted van der Waals Homostructures, Nature Physics.

Abstract:

Altermagnetism, characterized by compensated antiparallel spin order accompanied by finite spin splitting, bridges the properties of ferromagnets and antiferromagnets and holds promise for next-generation spintronic applications. Theoretical studies suggest that twisting van der Waals layers can induce altermagnetic states by tuning interlayer symmetry, thereby expanding the family of magnetic quantum materials. However, direct experimental observation of altermagnetism in these systems has not been achieved. Here, we demonstrate altermagnetism in orthogonally twisted CrPS₄/CrPS₄ homostructures using magneto-optical spectroscopy. This structure exhibits a ferromagnetic-like magnetic-field dependence of the degree of circular polarization. Furthermore, a pronounced Zeeman splitting—absent in either ferromagnetic or antiferromagnetic CrPS₄—emerges in the twisted configuration, indicating a distinct magnetic ground state. First-principles calculations reveal large spin-split bands in an antiferromagnetic configuration, confirming the realization of altermagnetism in twisted CrPS₄. Polarized Raman spectroscopy further identifies interlayer-coupling-induced phonon-mode splitting unique to the altermagnetic state. These findings provide experimental evidence of altermagnetism in a twisted van der Waals material.

Keywords: Altermagnetism, orthogonally twisted CrPS₄/CrPS₄, Zeeman splitting, Raman splitting, magneto-optical spectroscopy.

Link: https://www.nature.com/articles/s41567-026-03440-y

s41567-026-03440-y(6).pdf