Time-resolved x-ray imaging of nanoscale spin-wave dynamics at multi-GHz frequencies using low-alpha synchrotron operation
Time-resolved x-ray microscopy is used in a low-alpha synchrotron operation mode to image spin dynamics at an unprecedented combination of temporal and spatial resolution. Thereby, nanoscale spin waves with wavelengths down to 70 nm and frequencies up to 30 GHz are directly observed in ferromagnetic thin film microelements with spin vortex ground states. In an antiparallel ferromagnetic bilayer system, we detect the propagation of both optic and acoustic modes, the latter exhibiting even a strong non-reciprocity. In single-layer systems, quasi-uniform spin waves are observed together with modes of higher order (up to the 4th order), bearing precessional nodes over the thickness of the film. Furthermore, the effects of magnetic material properties, film thickness, and magnetic fields on the spin-wave spectrum are determined experimentally. Our experimental results are consistent with numerical calculations from a micromagnetic theory even on these so-far unexplored time- and length scales.
Authors
- Jörg Raabe (ORCID: https://orcid.org/0000-0002-2071-6896)
- Joachim Gräfe (ORCID: https://orcid.org/0000-0002-4597-5923)
- Joe Bailey (ORCID: https://orcid.org/0000-0002-1067-6560)
- Sina Mayr (ORCID: https://orcid.org/0000-0003-4614-9874)
- Johannes Förster (ORCID: https://orcid.org/0000-0001-7153-4833)
- J. Lindner (ORCID: https://orcid.org/0000-0002-4955-515X)
- Anna Semisalova (ORCID: https://orcid.org/0000-0002-9814-6758)
- A. K. Suszka
- Simone Finizio (ORCID: https://orcid.org/0000-0002-1792-0626)
- Georg Dieterle (ORCID: https://orcid.org/0000-0002-9042-9358)
- R. A. Gallardo (ORCID: https://orcid.org/0000-0002-4495-5592)
- Sebastian Wintz (ORCID: https://orcid.org/0000-0001-6138-8078)
- H. M. Stoll
- Markus Weigand (ORCID: https://orcid.org/0000-0002-0325-2268)
- Katrin Schultheiß (ORCID: https://orcid.org/0000-0002-3382-5442)
- R. Narkowicz (ORCID: https://orcid.org/0000-0003-4793-3281)
- Gisela Schütz
- E. Kirk
Institutions
- Johannes Gutenberg University Mainz (DE)
- Helmholtz-Zentrum Berlin für Materialien und Energie (DE)
- Helmholtz-Zentrum Dresden-Rossendorf (DE)
- Paul Scherrer Institute (CH)
- ETH Zurich (CH)
- Max Planck Institute for Intelligent Systems (DE)
- University of Duisburg-Essen (DE)
- Federico Santa María Technical University (CL)
Publication Details
- Journal
- Applied Physics Reviews
- Published
- 2024-10-22
- DOI
- https://doi.org/10.1063/5.0206576
- Citations
- 4
- Primary Topic
- Magnetic properties of thin films
- Type
- article
- Field-Weighted Citation Impact
- 1.35
Funders
- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
- Seventh Framework Programme
- Fondo Nacional de Desarrollo Científico y Tecnológico