Normal modes of coupled vortex gyration in two spatially separated magnetic nanodisks

  title={Normal modes of coupled vortex gyration in two spatially separated magnetic nanodisks},
  author={Kisuk Lee and Hyunsung Jung and Dong-Soo Han and Sang-Koog Kim},
  journal={Journal of Applied Physics},
We found from analytical derivations and micromagnetic numerical simulations that there exist two distinct normal modes in apparently complex vortex gyrotropic motions in two dipolar-coupled magnetic nanodisks. The normal modes have characteristic higher and lower single angular eigenfrequencies with their own elliptical orbits elongated along the x (bonding axis) and y axes, respectively. The superposition of the two normal modes results in coupled vortex gyrations, which depend on the… 

Figures and Tables from this paper

Gyration eigenfrequencies of vertically coupled vortices in layered magnetic disks
The dynamic properties of vertically coupled vortices in two magnetic nanodisks were studied using numerical simulations and analytical calculations. If the core polarizations of the two vortices are
Wave modes of collective vortex gyration in dipolar-coupled-dot-array magnonic crystals
Wave modes of collective vortex gyration in one-dimensional periodic arrays of magnetic disks using time-resolved scanning transmission x-ray microscopy are observed and Dispersion of the modes is found to be strongly affected by both vortex polarization and chirality ordering.
Perpendicular-bias-field control of coupled-vortex oscillations in nanodot networks
We studied, by combined micromagnetic numerical simulations and analytical derivations, coupled-vortex dynamics in one-dimensional (1D) arrays composed of two or more dipolar-coupled-vortex-state
Direct imaging of phase relation in a pair of coupled vortex oscillators
We study the magnetization dynamics in a stray-field coupled pair of ferromagnetic squares in the vortex state. Micromagnetic simulations give an idea of the mediating stray field during vortex
Vortex dynamics and frequency splitting in vertically coupled nanomagnets
Both experimental and micromagnetic simulations show that the frequency spectra for the combined system is significantly dependent on the chirality of the circular nanomagnet and is asymmetric with respect to the external bias field.
Contrasting vortex-gyration dispersions for different lattice bases in one-dimensional magnetic vortex arrays
We performed micromagnetic numerical and analytical calculations in studying the effects of change in the primitive unit cells of one-dimensional (1D) vortex arrays on collective vortex-gyration
Coupled gyration modes in one-dimensional skyrmion arrays in thin-film nanostrips as new type of information carrier
The coupled gyration modes of individual skyrmions might provide a new type of information carrier in narrow-width straight and curved nanostrips, as driven by magnetic interactions in such continuous thin films.
Coupled gyration modes and propagation in one-dimensional periodic skyrmion arrays as reliable information carrier
We report on a micromagnetic numerical simulation study of dynamic couplings between neighboring skyrmions in narrow-width nanostrips. We explored the coupled gyration modes and their characteristic
Enhanced gyration-signal propagation speed in one-dimensional vortex-antivortex lattices and its control by perpendicular bias field
We report on a micromagnetic simulation study of coupled core gyrations in one-dimensional (1D) alternating vortex-antivortex (V-AV) lattices formed in connected soft-magnetic-disk arrays. In such
A comparison of numerical simulations and analytical theory of the dynamics of interacting magnetic vortices
Magnetostatic interactions between vortices in closely spaced planar structures are important for applications including vortex-based magnonic crystals and spin torque oscillator networks. Analytical


Dynamics of coupled vortices in a pair of ferromagnetic disks.
These experimental results show that the coupled pair of vortices behaves similar to a diatomic molecule with bonding and antibonding states, implying a possibility for designing the magnonic band structure in a chain or an array of magnetic vortex oscillators.
Two circular-rotational eigenmodes and their giant resonance asymmetry in vortex gyrotropic motions in soft magnetic nanodots
We found, by micromagnetic numerical and analytical calculations, that the clockwise (CW) and counterclockwise (CCW) circular-rotational motions of a magnetic vortex core in a soft magnetic circular
Dynamics of magnetostatically coupled vortices in magnetic nanodisks
The dynamics of magnetostatically coupled vortices in two nanodisks is here investigated analytically and numerically. The rigid vortex model is employed to calculate the magnetostatic interaction
Coupled vortex oscillations in spatially separated permalloy squares.
It can be understood that only a weak response of the second vortex core is observed for equal core polarizations in pairs of micron-sized permalloy squares coupled via their stray fields.
Gyrotropic linear and nonlinear motions of a magnetic vortex in soft magnetic nanodots
The authors investigated the gyrotropic linear and nonlinear motions of a magnetic vortex in soft magnetic cylindrical nanodots under in-plane oscillating magnetic fields of different frequencies and
Eigenfrequencies of vortex state excitations in magnetic submicron-size disks
We have theoretically and numerically studied the dynamic properties of the vortex magnetic state in soft submicron ferromagnetic dots with variable thickness and diameter. To describe the vortex
FAST TRACK COMMUNICATION: Gyration mode splitting in magnetostatically coupled magnetic vortices in an array
We present the experimental observation of gyration mode splitting by the time-resolved magneto-optical Kerr effect in an array consisting of magnetostatically coupled Ni81Fe19 discs of 1 µm
Spin excitation frequencies in magnetostatically coupled arrays of vortex state circular Permalloy dots
Broadband ferromagnetic resonance in square arrays of Permalloy circular dots with different interdot separations was measured in the vortex ground state. The detected spin excitations show a
Dynamics of spin vortices in two-dimensional planar magnets
We investigate the dynamics of a dilute gas of free spin vortices in a two-dimensional planar magnet. An equation of motion for the spin vortex is presented and compared with the corresponding
Influence of dipolar interaction on vortex dynamics in arrays of ferromagnetic disks.
Transmission spectra reveal a strong dependence of the resonance frequency of vortex-core motion on the ratio between the center-to-center distance and the element size, and an analogy between the vortex system and rotating dipoles is confirmed by micromagnetic simulations.