Effect of Size and Bias Field on Spin-Wave Dynamics in Artificial Spin Ice*

Artificial spin-ice (ASI) lattices are lithographically defined nanostructures that exhibit remarkable magnetic and transport properties, enabling efficient control of spin dynamics [1]. Here, we present numerical simulations of magnetization dynamics in NiFe-based ASI using the micromagnetic simulation platform Ubermag [2], which is based on OOMMF. The ASI consists of stadium-shaped islands of 260x97x15 nm3 size arranged in arrays of 3×3, 5×5, and 10×10 primitive cells, with no periodic boundary conditions applied.

We varied the array size  while keeping all other parameters constant. Static micromagnetic simulations revealed nearly identical hysteresis loops for the three investigated array sizes, showing only slight variations in the saturation region. Dynamic simulations, with and without an external bias field, revealed a dominant mode at approximately 13.9 GHz. In the switching region, we observed additional modes arising from interactions between the nano islands. These results show that magnetic-field-induced reconfiguration of ASI arrays enables tunable control of spin-wave spectra, highlighting their potential for reconfigurable magnonic devices.