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

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.

SUBMITTER: Rao S

PROVIDER: S-EPMC4448658 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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

Rao Siddharth S Rhensius Jan J Bisig Andre A Mawass Mohamad-Assaad MA Weigand Markus M Kläui Mathias M Bhatia Charanjit S CS Yang Hyunsoo H

Scientific reports 20150529

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 structur ...[more]

PMID: 26023723

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