Magnetodynamic properties of dipole-coupled 1D magnonic crystals

TL;DR

This paper investigates the magnetodynamic behavior of 1D magnonic crystals made of NiFe strips, using a macrospin model to accurately predict experimental and micromagnetic results, revealing insights into damping and linewidth broadening.

Contribution

It introduces a simple macrospin model with a single adjustable parameter to accurately describe the magnetodynamic properties of dipole-coupled 1D magnonic crystals.

Findings

The macrospin model fits experimental and micromagnetic data well.

Gilbert damping is independent of lattice constant.

Linewidth broadening increases as stripe separation decreases.

Abstract

Magnonic crystals are magnetic metamaterials, that provide a promising way to manipulate magnetodynamic properties by controlling the geometry of the patterned structures. Here, we study the magnetodynamic properties of 1D magnonic crystals consisting of parallel NiFe strips with different strip widths and separations. The strips couple via dipole-dipole interactions. As an alternative to experiments and/or micromagnetic simulations, we investigate the accuracy of a simple macrospin model. For the case of simple strips, a model with a single free parameter to account for an overestimation of the out-of-plane demagnetization of the magnonic lattice is described. By adjusting this parameter a good fit with experimental as well as micromagnetic results is obtained. Moreover, the Gilbert damping is found independent of the lattice constant however the inhomogeneous linewidth broadening found to increase with decreasing stripe separation.