Spin waves in magnetic nanodisks, nanorings, and 3D nanovolcanoes

TL;DR

This paper reviews the study of standing spin waves in various patterned magnetic nanostructures, highlighting advancements in ferromagnetic resonance techniques from arrays to individual elements and from planar to 3D geometries.

Contribution

It provides a comprehensive overview of the evolution of FMR studies on magnetic nanostructures, emphasizing the transition from array-based to single-element analysis and from 2D to 3D geometries.

Findings

Development of broadband FMR for individual nanostructures

Observation of spin wave modes in 3D nanovolcanoes

Progress in downscaling from arrays to single elements

Abstract

Patterned magnetic nanostructures are advanced materials characterized by their unique magnetic properties at the nanoscale, which are the result of tailored geometric configurations and compositional engineering. As interest in nanotechnology continues to grow exponentially, the exploration of patterned magnetic nanostructures turns into a vibrant and critical area of study for both industry professionals and academic researchers. Here, we review investigations of standing spin waves (collective spin precessions) in magnetic elements by the technique of ferromagnetic resonance (FMR). The presentation encompasses earlier studies of arrays of magnetic nanodisks and nanoringes by cavity-based FMR as well as more recent studies of individual nanodisks and 3D nanovolcanoes by a broadband FMR method which implies the use of a coplanar waveguide. Overall, the manuscript outlines the development of FMR studies along the two major lines: (i) downscaling from multiple to individual magnetic nanoelements and (ii) extending planar nanomagnets into the third dimension.