Magnonics Crystal Composed by Magnetic Antivortices Confined in Antidots

A magnetic patterned system constituted by antidots has been synthesized by electron beam lithography and its static and dynamical properties have been studied. Magnetic-domain patterns related to the static hysteresis loop have been acquired by means of magnetic force microscopy. The dynamical response to a magnetic field pulse has been studied by means of micromagnetic simulations. We found the magnetic response of a single antidot (excitation of a single mode) is qualitatively different from the one of coupled antidots (excitation of two modes). In the latter configuration, micromagnetic simulations show the low-frequency mode related to the in-phase oscillation of the magnetization and the high-frequency mode related to the out-of-phase oscillation of the magnetization.