Edge localization of spin waves in antidot multilayers with perpendicular magnetic anisotropy

Abstract

We study the spin-wave dynamics in nanoscale antidot lattices based on Co/Pd\nmultilayers with perpendicular magnetic anisotropy. Using time-resolved\nmagneto-optical Kerr effect measurements we demonstrate that the variation of\nthe antidot shape introduces significant change in the spin-wave spectra,\nespecially in the lower frequency range. By employing micromagnetic simulations\nwe show that additional peaks observed in the measured spectra are related to\nnarrow shell regions around the antidots, where the magnetic anisotropy is\nreduced due to the Ga+ ion irradiation during the focused ion beam milling\nprocess of the antidot fabrication. The results point at new possibilities for\nexploitation of localized spin waves in out-of-plane magnetized thin films,\nwhich are easily tunable and suitable for magnonics applications.\n