- Open Access
Propagation and localization of spin excitations at altermagnetic domain walls
Phys. Rev. B 114, 194421 – Published 23 October, 2026
DOI: https://doi.org/10.1103/zgw5-99k2
Abstract
Altermagnets () are spin-compensated materials in which opposite-spin sublattices are connected by a symmetry that causes a spin splitting in their elementary excitations. As there is a strong effect of altermagnetism on domain wall properties, it is quite natural to also expect an enrichment of the physics of magnetic excitations at domain walls. Here, we consider the propagation of spin eigenexcitations along domain walls in easy-axial -wave . Investigating the presence of bound states localized on a domain wall, we find that the effect of the on the bound states strongly depends on the orientation of the domain wall relative to the crystallographic directions. If the domain wall is oriented along a nodal direction [100] or [010], does not change the number of bound states; however, it leads to a nonlinear dispersion and a tilt of the wavefront. The effect of is strongest when the domain wall is oriented along the directions [110] or , i.e., along the directions of the strongest splitting in the magnon spectrum. In this case, (i) the additional gapped bound states appear, (ii) degeneracy of the eigenstates with respect to their polarization (right-hand or left-hand precession of the Néel vector) is removed, and (iii) the localization area of the bound states strongly depends on the eigenfrequency. The latter may lead to strong localization of the bound state at the domain wall. We further consider the influence of a static magnetic field that is applied along the easy axis and find that the magnetic field induces an asymmetry between the localization regions on opposite sides of the domain wall and sets an upper limit on the absolute value of the propagating eigenstate's wave vector.
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