Adjustable and switchable magnetic high-frequency properties - domain configurations and observation of magnetization dynamics of structured ferromagnetic layers

The project focuses on the correlation of artificially generated magnetic domains and domain wall configurations with the magneto-dynamic response in magnetic micro-and nanostructured thin films. Large area thin film nanoscale structures and thus novel effective magnetic media will be produced, the effective magnetic properties of which will be varied by different imprinted magnetization configurations. The variable remanent magnetization configurations are set by periodic nanostructures and magneto-thermal methods. Different approaches to the fabrication of domain engineered structures will be studied. Using various methods of domain control, novel ways to adjust the magnetic permeability and the spin-wave behavior of magnetic structures will be investigated.

Essentially, new principles for optimized functionality in the area of magnetic sensors and magnetization dynamics are created. The main focus of the current studies is on switchable magnetic high-frequency characteristics of large surface nanoscale structures.

Adjustable high-frequency properties at DFG Gepris.

References

1. U. Urdiroz, C. Müller, A. Gomez, M. Magaz, D. Granados, M. Sánchez Agudo, J. Rubio-Zuazo, G.R. Castro, C. Stan, N. Tamura, H.A. Padmore, F. Cebollada, F.J. Palomares, J. McCord, J.M. González, Spin waves excitation at micron-sized, anisotropy modified regions in amorphous Fe₈₀B₂₀ stripes: local properties, inter-regions coupling and phase-shift induction, Materials Science and Engineering B. 271, 115258 (2021) 
2. U. Urdiroz, A. Gómez, M. Magaz, D. Granados, M. Sánchez Agudo, J. Rubio-Zuazo, G.R. Castro, C. Stan, N. Tamura, H.A. Padmore, C. Müller, J. McCord, F. Cebollada, F.J. Palomares, J.M. González, Antiphase resonance at X-ray irradiated microregions in amorphous Fe₈₀B₂₀ stripes, Journal of Magnetism and Magnetic Materials 520, 167017 (2021)
3. M. Lohman, B. Mozooni, J. McCord, Homogeneous microwave field emitted propagating spin waves: Direct imaging and modeling, Journal of Magnetism and Magnetic Materials 450, 7 (2018) 
4. R.B. Holländer, C. Müller, M. Lohmann, B. Mozooni, J. McCord, Component selection in time-resolved magneto-optical wide-field imaging for the investigation of magnetic microstructures, Journal of Magnetism and Magnetic Materials 432, 283–290 (2017)
5. B. Mozooni, J. McCord, Direct observation of closure domain wall mediated spin-waves, Applied Physics Letters 107, 042402 (2015) 
6. B. Mozooni, T. von Hofe, J. McCord, Picosecond wide-field magneto-optical imaging of magnetization dynamics of amorphous film elements, Physical Review B 90, 054410 (2014)
7. C. Hengst, M. Wolf, R. Schäfer, L. Schultz, J. McCord, Acoustic-domain resonance mode in magnetic closure-domain structures: A probe for domain-shape characteristics and domain-wall transformations, Physical Review B 89, 214412 (2014) 
8. C. Hamann, R. Mattheis, I. Mönch, J. Fassbender, L. Schultz, J. McCord, Magnetization dynamics of magnetic domain wall imprinted magnetic films, New Journal of Physics 16, 023010 (2014)
9. J. McCord, S. Mangin,  Separation of low- and high-temperature contributions to the exchange bias in Ni₈₁Fe₁₉-NiO thin films,  Physical Review B 88, 014416  (2013) 
10. C. Patschureck, K. Lenz, M. O. Liedke, M. U. Lutz, T. Strache, I. Mönch, R. Schäfer, L. Schultz, and J. McCord, Magnetization dynamics of buckling domain structures in patterned thin films, Physical Review B 86, 054426 (2012)