Figure 1

Concept of resonant amplification of vortex oscillations by coherent serial pulses.

(a) Top: Perspective-view image and cross-section of magnetic vortex state. The color and height of the surface indicate the in-plane and out-of-plane components of local magnetizations, respectively. Bottom: Potential energy surface and analytically calcualted vortex-core trajectories. The vortex-core trajectories under the Gaussian-pulse train (pulse number N = 2) are plotted on the potential energy surface. For the cases I and II, the time intervals employed were and , respectively. The blue and red lines indicate the trajectories of vortex-core positions driven by the first and second pulses, respectively (see the pulse profiles in (b)). (b) Profiles of train of Gaussian-pulse currents along single-strip electrode with pulse width (σ), time interval (ΔT) and pulse number (N = 4).