Field-Tuned Spin Excitation Spectrum of Magnetic 2π Radial Vortex

The 2π radial vortex is defined by its switching angle of magnetization from the center to the boundary, which is equal to 2π. This work investigates the different spin-wave modes of a 2π radial vortex in a nanodisk under the sinc-function excitation magnetic field using micromagnetic simulation. It is found that the four in-plane and three out-of-plane eigenfrequencies correspond to clockwise rotation modes, counterclockwise rotation modes, and breathing modes. Moreover, the inner and outer diameters of different magnetization distribution regions are both adjusted when a static magnetic field is applied to the nanodisk, and the eigenfrequencies are determined as a function of the amplitude. These results exhibit the rich spin-wave modes of the 2π radial vortex and provide the possibility of applications in magnonics and spintronic devices.