Magnetic vortex core reversal by excitation of spin waves

Magnetic vortex core reversal by excitation of spin waves.
Matthias Kammerer, Markus Weigand, Michael Curcic, Matthias Noske, Markus Sproll, Arne Vansteenkiste, Bartel Van Waeyenberge, Hermann Stoll, Georg Woltersdorf, Christian H. Back & Gisela Schuetz
Nature Comms 2, 279 (2011)

The legend (c) shows microscopy images of X-ray transmission through the inner part (150 nm×150 nm) of the sample indicating the vortex core polarity (white: vortex up; black: vortex down) before and after a field burst. The phase diagrams show the points (excitation amplitude versus frequency) where vortex core reversal from up to down was observed in the experiments (a) and the simulations (b).