Dynamics of reconfigurable artificial spin ice: towards magnonic functional materials

TL;DR

This paper reviews the potential of reconfigurable artificial spin ices as magnonic materials, emphasizing their dynamic behavior, reconfigurability, and applications in spin wave-based logic and magnonic crystals.

Contribution

It provides a comprehensive overview of recent advances in reconfigurable artificial spin ices for magnonic applications, highlighting new techniques and geometries for reconfigurability.

Findings

Artificial spin ices exhibit rich mode spectra in the GHz range.

Reconfigurability is crucial for their application as magnonic crystals.

Various methods enable spectral response analysis of spin ices.

Abstract

Over the past few years, the study of magnetization dynamics in artificial spin ices has become a vibrant field of study. Artificial spin ices are ensembles of geometrically arranged, interacting magnetic nanoislands, which display frustration by design. These were initially created to mimic the behavior in rare earth pyrochlore materials and to study emergent behavior and frustration using two-dimensional magnetic measurement techniques. Recently, it has become clear that it is possible to create artificial spin ices, which can potentially be used as functional materials. In this Perspective, we review the resonant behavior of spin ices (which is in the GHz frequency range), focusing on their potential application as magnonic crystals. In magnonic crystals, spin waves are functionalized for logic applications by means of band structure engineering. While it has been established that artificial spin ices can possess rich mode spectra, the applicability of spin ices to create magnonic crystals hinges upon their reconfigurability. Consequently, we describe recent work aiming to develop techniques and create geometries allowing full reconfigurability of the spin ice magnetic state. We also discuss experimental, theoretical, and numerical methods for determining the spectral response of artificial spin ices, and give an outlook on new directions for reconfigurable spin ices.