2024/11/18 by Sopheak Sorn, Sorn, Sopheak · 2 citations
Physics and Astronomy · #FOS: Physical sciences #Magnetic properties of thin films #Materials Science (cond-mat.mtrl-sci) #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Physics of Superconductivity and Magnetism #Topological Materials and Phenomena
paper · pdf · doi:10.48550/arxiv.2411.11949
openalex publication_date 2024/11/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We study surface states and domain wall bound states in altermagnets using a rutile-lattice tight-binding model of electrons coupled to a Néel order. We discover that two symmetry-protected Weyl nodal lines in the bulk band structure can give rise to unconventional anti-chiral surface states -- surface states from opposite surfaces propagate in a parallel manner, as opposed to the anti-parallel manner for the more conventional chiral surface states. We also find that the anti-chiral surface states can be turned into chiral surface states upon changing the surface termination. The origin of the surface states, the dependence on the surface termination, and key features of domain wall bound states are explained using a map from the altermagnet to a family of a modified Su-Schrieffer-Heeger(SSH) chain and the associated bulk-boundary correspondence. Our work reveals rutile altermagnets as a promising candidate among very few quantum materials that can support anti-chiral surface states.