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DOE OSTI · 1608833

Non-standing spin-waves in confined micrometer-sized ferromagnetic structures under uniform excitation

Pile, S.·Feggeler, T.·Schaffers, T.·Meckenstock, R.·Buchner, M.·Spoddig, D.·Zingsem, B.·Ney, V.·Farle, M.·Wende, H.·Ohldag, H.·Ney, A.·Ollefs, K.
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Abstract

A non-standing characteristic of directly imaged spin-waves in confined micrometer-sized ultrathin Permalloy (Ni 80 Fe 20 ) structures is reported along with evidence of the possibility to alter the observed state by modifications to the sample geometry. Using micromagnetic simulations, the presence of the spin-wave modes excited in the Permalloy stripes along with the quasi-uniform modes was observed. The predicted spin-waves were imaged in direct space using time resolved scanning transmission x-ray microscopy, combined with a ferromagnetic resonance excitation scheme (STXM-FMR). STXM-FMR measurements revealed a non-standing characteristic of the spin-waves. Also, it was shown by micromagnetic simulations and confirmed using STXM-FMR results that the observed characteristic of the spin-waves can be influenced by the local magnetic fields in different sample geometries.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

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Pile, S., Feggeler, T., Schaffers, T., Meckenstock, R., Buchner, M., Spoddig, D., Zingsem, B., Ney, V., Farle, M., Wende, H., Ohldag, H., Ney, A., Ollefs, K.. 2020-02-18. Non-standing spin-waves in confined micrometer-sized ferromagnetic structures under uniform excitation. https://doi.org/10.1063/1.5139881

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