Classification of magnetism and altermagnetism in quasicrystals

作者：Zhi-Yan Shao, Jia-Heng Ji, Chen Lu, Zhiming Pan, Yubo Liu, Fan Yang · 发表于：npj Computational Materials · 年份：2026 · DOI：10.1038/s41524-026-02309-1 · 被引用次数：1 · 研究领域：Quasicrystal Structures and Properties、Topological Materials and Phenomena、Advanced Condensed Matter Physics

Altermagnetism (AM), an unconventional magnetic phase characterized by zero net magnetism protected by symmetry(s) other than parity-time ( \({\mathcal{P}}{\mathcal{T}}\) ) and a resulting spin-split band, has been studied exclusively in crystalline materials. Here, we extend the framework of AM to quasicrystals (QCs). We start from a comparison between the Néel state on the square lattice and that on a D 4 -symmetric Thue-Morse QC, with the latter obtained from solving a half-filled bipartite Hubbard model through the sign-problem-free projector quantum Monte Carlo algorithm. Consequently, although both Néel states belong to the same d -wave irreducible representation (IRRP) of the D 4 point group, they belong to different magnetic classes: The former Néel state is antiferromagnetism (AFM) protected by the combined \({\mathcal{P}}{\mathcal{T}}\) and translational symmetry, while the lack of translational symmetry in the latter Néel state breaks the \({\mathcal{P}}{\mathcal{T}}\) symmetry, and the additional mirror or rotation symmetry protects AM. This example suggests that AM is more common in QCs than in crystals and can be easily explored through a point-group symmetry-based classification. Therefore, we classify colinear magnetic phases in 2D D n -symmetric QCs without spin-orbit coupling, by using IRRPs of D n . Consequently, the identity IRRP represents ferromagnetism, the inversion-odd 1D IRRPs for twice-of-odd n represent AFM, and all the remaining 1D IRRPs represent...