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arXiv · 1505.07936

Time-resolved imaging of pulse-induced magnetization reversal with a microwave assist field

Siddharth Rao·Jan Rhensius·Andre Bisig·Mohamad-Assaad Mawass·Markus Weigand·Mathias Klaui·Charanjit S. Bhatia·Hyunsoo Yang
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Abstract

The reversal of the magnetization under the influence of a field pulse has been previously predicted to be an incoherent process with several competing phenomena such as domain wall relaxation, spin wave-mediated instability regions, and vortex-core mediated reversal dynamics. However, there has been no study on the direct observation of the switching process with the aid of a microwave signal input. We report a time-resolved imaging study of magnetization reversal in patterned magnetic structures under the influence of a field pulse with microwave assistance. The microwave frequency is varied to demonstrate the effect of resonant microwave-assisted switching. We observe that the switching process is dominated by spin wave dynamics generated as a result of magnetic instabilities in the structures, and identify the frequencies that are most dominant in magnetization reversal.

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Siddharth Rao, Jan Rhensius, Andre Bisig, Mohamad-Assaad Mawass, Markus Weigand, Mathias Klaui, Charanjit S. Bhatia, Hyunsoo Yang. 2015-05-29. Time-resolved imaging of pulse-induced magnetization reversal with a microwave assist field. https://arxiv.org/abs/1505.07936

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