Physical Review B
We report a time-resolved imaging and micromagnetic simulation study of the relaxation dynamics of a magnetic vortex in the nonlinear regime. We use time-resolved photoemission electron microscopy and micromagnetic calculations to examine the emergence of nonlinear vortex dynamics in patterned Ni80Fe20 disks in the limit of long field pulses. We show for core shifts beyond ∼20%–25% of the disk radius, the initial motion is characterized by distortions of the vortex, a transient cross-tie wall state, and instabilities in the core polarization that influence the core trajectories.
© 2009 by the American Physical Society. The publisher's version of the article can be found at http://prb.aps.org/abstract/PRB/v79/i17/e172411.
X. M. Cheng et al., Physical Review B 79, 172411 (2009).