Numerical calculation of spin wave dispersions in magnetic nanostructures

We present the numerical calculations of spin wave dispersions in magnetic nanostructures. The dispersion is obtained by processing the space-time data calculated using the finite difference method based micromagnetic simulations. Various issues related to the calculation of the two-dimensional fast Fourier transform and methods to obtain high-quality dispersion curves are discussed. The spatial profile of the spin wave modes is also presented. The method is validated by applying it to various nanomagnetic systems including magnetic nanostripes, magnetic nanowires and confined thin film elements. Further, we calculate the magnonic dispersions in simple 1D and 2D magnonic crystals based on magnetic anti-dot arrays. (paper)