Role of boundaries in micromagnetic calculations of magnonic spectra of arrays of magnetic nanoelements
Physical Review B - Condensed Matter and Materials Physics
American Physical Society
This is the final version of the article. Available from American Physical Society via the DOI in this record.
We have used micromagnetic simulations performed with open and periodic boundary conditions to study the influence of the presence of array boundaries on the spectra and spatial profiles of collective spin-wave excitations in arrays of magnetic nanoelements. The spectra and spatial profiles of collective spin waves excited in isolated arrays of nanoelements and those forming a part of quasi-infinite arrays are qualitatively different even if the same excitation field is used in the simulations. In particular, the use of periodic boundary conditions suppresses the excitation of nonuniform collective modes by uniform excitation fields. However, the use of nonuniform excitation fields in combination with periodic boundary conditions is shown to enable investigation of the structure of magnonic dispersion curves for quasi-infinite arrays (magnonic crystals) in different directions in the reciprocal space and for different magnonic bands. The results obtained in the latter case show a perfect agreement with those obtained with the dynamical matrix method for infinite arrays of nanoelements of the same geometry and magnetic properties. © 2013 American Physical Society.
The research leading to these results has received funding from the ECs 7th Framework Programme (FP7/2007-2013) under Grant No. 233552 (DYNAMAG) and from EPSRC of the UK under Project No. EP/E055087/1.
Phys. Rev. B 87, 174422