Collinear altermagnetism for 3D chiral higher-order topological insulators
Abstract
Despite significant progress in the study of higher-order topological insulators (HOTIs), the chiral C4𝒯-protected HOTI has remained elusive in electronic materials, where C4𝒯 denotes the product of a four-fold rotation and time-reversal symmetry. We show that altermagnetism, a recently discovered form of collinear magnetism, provides a new route to realize this elusive phase. Specifically, we construct a microscopic model that combines a three-dimensional topological insulator with a collinear d-wave altermagnet on a Lieb lattice. Through analytical and numerical calculations, we show that the magnetism shifts and gaps the surface Dirac cones to produce the desired chiral hinge channels. Finally, we identify promising material classes to realise our proposal. Our results establish collinear altermagnetism as a route to intrinsic chiral higher-order topology and open a new path toward the discovery of C4𝒯-protected HOTIs in real materials.
Related
- Altermagnetism-induced higher-order topological Dirac semimetals in two-dimensional nonsymmorphic systems
- Anti-higher-order topological insulators
- Collinear and Coplanar Altermagnetism in a Penrose Quasicrystal
- Divergent Orbital Diamagnetism from Chiral Edge States in Chern Insulators
- Soft-Collinear Chiral Perturbation Theory for B → π form factors at large recoil
BibTeX
@misc{hadjipaschalis2026collinear,
title = {{Collinear altermagnetism for 3D chiral higher-order topological insulators}},
author = {Andreas Hadjipaschalis and Jennifer Cano},
howpublished = {arXiv},
year = {2026},
month = aug,
doi = {10.48550/arxiv.2608.27552},
eprint = {2608.27552},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2608.27552},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Collinear altermagnetism for 3D chiral higher-order topological insulators
AU - Andreas Hadjipaschalis
AU - Jennifer Cano
PY - 2026
DA - 2026/08/27
PB - arXiv
DO - 10.48550/arxiv.2608.27552
UR - https://arxiv.org/abs/2608.27552
AB - Despite significant progress in the study of higher-order topological insulators (HOTIs), the chiral C_4𝒯-protected HOTI has remained elusive in electronic materials, where C_4𝒯 denotes the product of a four-fold rotation and time-reversal symmetry. We show that altermagnetism, a recently discovered form of collinear magnetism, provides a new route to realize this elusive phase. Specifically, we construct a microscopic model that combines a three-dimensional topological insulator with a collinear d-wave altermagnet on a Lieb lattice. Through analytical and numerical calculations, we show that the magnetism shifts and gaps the surface Dirac cones to produce the desired chiral hinge channels. Finally, we identify promising material classes to realise our proposal. Our results establish collinear altermagnetism as a route to intrinsic chiral higher-order topology and open a new path toward the discovery of C_4𝒯-protected HOTIs in real materials.
ER -