Effect of Hole Shape on Spin-Wave Band Structure in One-Dimensional Magnonic Antidot Waveguide

TL;DR

This study demonstrates how varying the shape of antidots in a nanoscale magnonic waveguide can tune the spin-wave band structure, especially the bandgaps, by analyzing magnetic configurations and exchange field inhomogeneities.

Contribution

It introduces a method to control spin-wave bandgaps in magnonic waveguides through antidot shape variation, advancing magnonic crystal design.

Findings

Antidot shape significantly affects spin-wave dispersion.

Exchange field inhomogeneity influences band structure control.

Shape variation enables tunable magnonic bandgaps.

Abstract

We present the possibility of tuning the spin-wave band structure, particularly the bandgaps in a nanoscale magnonic antidot waveguide by varying the shape of the antidots. The effects of changing the shape of the antidots on the spin-wave dispersion relation in a waveguide have been carefully monitored. We interpret the observed variations by analysing the equilibrium magnetic configuration and the magnonic power and phase distribution profiles during spin-wave dynamics. The inhomogeneity in the exchange fields at the antidot boundaries within the waveguide is found to play a crucial role in controlling the band structure at the discussed length scales. The observations recorded here will be important for future developments of magnetic antidot based magnonic crystals and waveguides.