Figure 4. Snapshots of the 'dip' structures.

The out-of-plane magnetization of the central part extracted from the 1.6-μm disc before the core reversal. (a) A section of 300 nm in diameter showing the excited azimuthal spin wave modes as well as the 'dip'. The dynamics of modes with the same rotation sense are similar in the number of 'dips' and in their phase relation to the vortex core. This is indicated by the arrows below the snapshots. The difference between oppositely rotating modes are the result of the symmetry breaking due to the gyrofield. (b) For comparison the central part of the same structure with 500 nm in diameter is given, excited at the gyrotropic resonance. This results in a much larger trajectory of the core and the 'dip'. The black bars correspond to a lateral size of 100 nm in both cases (a, b).