Coupled vortex oscillations in mesoscale ferromagnetic double-disk structures

Coupled resonance modes in connected ferromagnetic double-dot structures have been investigated as a function of the overlap between the dots, both experimentally and via micromagnetic simulations. An asymmetry is observed in the frequency spectrum about zero field. Softening of the magnetization during vortex core precession when the cores are near the overlap region results in low-frequency modes and a splitting corresponding to different polarity combinations. A range of vortex resonance frequencies are identified that can be tuned by varying the overlap area. This study provides insight into the control of the dynamic response in coupled mesoscale magnetic structures.