Recently, as a potential candidate of next-generation signal-transfer device, the dynamics of coupled magnetic vortices have been studied. One of the required features of future devices is high working speed, but the previous results of signal-transfe...
Recently, as a potential candidate of next-generation signal-transfer device, the dynamics of coupled magnetic vortices have been studied. One of the required features of future devices is high working speed, but the previous results of signal-transfer speed of an array of separated vortex disks were relatively lower than other candidates.
In this thesis, we introduced the connected disks structure, where a magnetic vortex and antivortex are formed in turn. They are strongly coupled via not only a long-range dipole-dipole interaction, but also a short range exchange interaction. We observed the signal transfer phenomena by way of gyration propagation of the coupled vortex-antivortex array, and revealed that the collective oscillations of the cores’ gyration were decomposed by fundamental modes, described as standing waves. In addition, we found two unique branches of band structures, which imply that the dynamics of the vortex-antivortex array acts as the diatomic lattice vibration.
We also demonstrated the control of gyration propagation speed by application of a perpendicular magnetic field. The gyration propagation speed for the parallel polarization ordering is much faster (>1 km/s) than that for the 1D vortex-state arrays.
This work provides a fundamental understanding of the coupled dynamics of topological solitons, as well as an additional mechanism for fast gyration-signal propagation; moreover, it offers an efficient means of significant propagation-speed enhancement that is suitable for information carrier applications in continuous thin-film nanostrips.