Wave dynamics in a macroscopic square artificial spin ice

A macroscopic square artificial spin ice (ASI) is a collection of bar magnets placed in a square lattice arrangement. Each magnet is supported by hinges that allow its mechanical rotation. Previous investigations in these structures have shown ground-state configurations and driven dynamics similar to those of their nanosized counterparts. Here we numerically investigate the impact of the wave dynamics of a uniform state and the impact of a domain wall on the driven dynamics. We find that waves quickly lose coherence by scattering between modes in this system. In addition, we observe a distinct mode associated with the isolated oscillation at the domain wall. As expected from spatial localization, this resonant mode is under the band of propagating waves in the macroscopic square ASI. The results are analogous to the development of low-frequency edge modes in nanoscopic spin ices in the presence of defects. Our results provide valuable insight into the physics of mechanomagnetic systems, demonstrating the existence of wave scattering and spatial confinement phenomena in macroscopic square ASIs.