In this paper, we propose a standard micromagnetic problem, of a nanostripe of permalloy. We study the magnetization dynamics and describe methods of extracting features from simulations. Spin wave dispersion curves, relating frequency and wave vector, are obtained for wave propagation in different directions relative to the axis of the waveguide and the external applied field. Simulation results using both finite element (Nmag) and finite difference (OOMMF) methods are compared against analytic results, for different ranges of the wave vector. © 1965-2012 IEEE.

Anil Prabhakar

Department of Electrical Engineering

Applied field

Extracting features

Finite difference

Finite element

Magnetization dynamics

MICROMAGNETICS

Wave dispersion

WAVE VECTOR

Dispersion (waves)

Magnetic recording

Waveguides

Spin waves

Fulltext

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IIT Madras

Proposal for a Standard Micromagnetic Problem: Spin Wave Dispersion in a Magnonic Waveguide

IEEE Transactions on Magnetics

The dispersion relation of forward volume dipolar spin waves in a magnonic curved waveguide is investigated by solving Walker's equation in cylindrical coordinates with appropriate boundary conditions. Dispersion for exchange spin waves is then calculated using an iterative method. We validate our results by comparing the dispersion relation for higher bending radius with that of a straight waveguide. We also observe good agreement with the dispersion plots from micromagnetic simulations. For a ring, we impose periodic boundary conditions along the azimuthal direction to obtain standing wave mode patterns. The frequency-mode number characteristics of standing waves follow the dispersion relation for propagating spin waves in a curved waveguide. The maximum spin wave amplitude is not necessarily at the center of the waveguide. Exchange interactions cause the maximum to occur at a lower radius for higher mode numbers. © 1965-2012 IEEE.

An iterative solution for spin-wave dispersion in a magnonic ring

We simulate spin wave (SW) dynamics in a thin film antidot magnonic crystal (MC) with a ring defect. An external magnetic field is applied perpendicular to the film plane in a forward volume configuration. We initially use the plane wave method to obtain the SW band diagram for the antidot MC structure (without the defect), which gives us an idea of modes that are trapped in the crystal. We then use finite element micromagnetic simulations to study the SW propagation in the MC with the ring defect. The power spectral density of the magnetization at the top of the ring shows peaks that fall within the band gap of the MC. The SW energy in other frequency components is dissipated in the MC and do not reach the other end of the ring. © 2014 IEEE.

Micromagnetic and plane wave analysis of an antidot magnonic crystal with a ring defect

A Fast Finite-Difference Method for Micromagnetics Using the Magnetic Scalar Potential

Journal of Physics D: Applied Physics

Numerical calculation of spin wave dispersions in magnetic nanostructures

Physical Review B

Dispersion of collective magnonic modes in stacks of nanoscale magnetic elements

Efficiency of the Geometric Integration of Landau–Lifshitz–Gilbert Equation Based on Cayley Transform

Journal of Applied Physics

Micromagnetic method of s-parameter characterization of magnonic devices

Proposal for a standard micromagnetic problem: Spin wave dispersion in a magnonic waveguide

Journal	IEEE Transactions on Magnetics
ISSN	00189464
Open Access	Yes