Magnon Superlattices around Skyrmions in Frustrated Magnets

Abstract: Dynamic and stable magnetic textures offer a powerful platform for controlling magnon states in the broader context of spin electronics. In this work, we uncover a novel class of dynamical, crystal-like localization patterns in real space, arising from the hybridization of magnons with topologically non-trivial spin textures that possess helicity as an internal degree of freedom. By tuning the magnon wavelength to match the size of these textures, specifically, atomic-scale skyrmions in centrosymmetric frustrated magnets, we achieve strong interference effects. This leads to the emergence of magnon superlattices, shaped by the internal skyrmion structure and the underlying Mexican-hat magnon dispersion. Furthermore, helicity-driven nonlinear dynamics give rise to dispersive magnon bands with nontrivial Chern numbers within the first magnon gap. These findings provide fundamental insights into magnon behavior in complex spin environments and establish frustrated magnets as a versatile platform for manipulating spin excitations at the atomic scale.