Dipolar coupling effect on magnetization dynamics in artificial kagome spin ices

The study of spin dynamics in artificial spin ice (ASI) has in recent years become a vibrant research field for reconfigurable magnonics. We present experimental and theoretical studies of magnetization dynamics in disconnected kagome ASI lattices using broadband ferromagnetic resonance and micromagnetic simulations. By systematically varying the field strength and orientation, the dynamical coupling effects between different ASI sublattices have been distinguished for the field along the symmetric axes. For the field parallel to one sublattice bar, the mode hybridization with an avoided-crossing gap is identified, and a special dynamical magnon mode emerges. But, for the field perpendicular to one sublattice bar, the magnon modes from the other two sublattice bars merge into a single mode, which is attributed to the static dipolar interactions between the sublattice bars. Our research shows a detailed investigation of magnetization dynamics in kagome ASIs, which is of great significance to further understand collective spin-dynamics behavior in nanomagnet systems.