Ferromagnetic resonance in 3D-tilted square artificial spin ices

TL;DR

This study investigates the ferromagnetic resonance properties of three-dimensional square artificial spin ices, comparing semi-analytical and micromagnetic simulation methods to understand their spectral features and tunability.

Contribution

It introduces a numerical analysis of 3D-tilted square ASIs, highlighting the advantages and limitations of semi-analytical and micromagnetic approaches for their dynamic behavior.

Findings

Qualitative agreement between methods on spectral features

Spectral tunability as a function of tilt angle

Limitations due to model simplifications and computational resolution

Abstract

Artificial spin ices (ASIs) arranged in square formations have been explored from the perspective of reconfigurable magnonics. A new frontier in ASIs is their three-dimensional (3D) extension. Here, we numerically explore the ferromagnetic resonance of square ASIs as each nanomagnet is rotated out of plane into 3D ASIs, in which the vertex gap can be either kept constant or varying. We study both remanent and vortex configurations using a semi-analytical dynamic approach and micromagnetic simulations. We find that both methods show qualitative agreement of the main spectral features. However, there are important limitations. On one hand, the semi-analytical approach relies on a minimal model of the demag field, preventing exact predictions. On the other hand, micromagnetic simulations suffer from sufficient resolution, making the results grid-dependent and extremely slow. Regardless, both methods display tunability as a function of the tilt angle. These results showcase advantages and limitations of both methods and are promising to further our understanding of 3D ASI dynamics.