Spatial distribution of spin-wave modes in cylindrical nanowires of finite aspect ratio

The spin-wave modes of cylindrical nanowires of moderate diameter-to-length ratios are investigated in this paper. Based on three-dimensional simulations and analytical calculations we determine the spatial structures of the modes. We show that standing spin waves and localized edge modes form the discrete spectrum of the nanowires. Using a simple analytical model we infer an extended dispersion relation for spin waves in cylinders. Considering the variation of the demagnetizing (internal) field we show that the localized dipole-exchange modes at the edges are always present.