FMR Damping in Thin Films with Exchange Bias

Nikolay G. Chechenin, Irina O. Dzhun, Georgy V. Babaytsev, Mikhail G. Kozin, Alexey V. Makunin, Irina L. Romashkina
2021 Magnetochemistry  
Ferromagnetic resonance (FMR) linewidth (LW) is a tool for studying the high frequency properties of magnetic materials for their application in high-speed devices. Here, we investigate different mechanisms which determine FMR damping in bilayer ferromagnetic/antiferromagnetic (F/AF and AF/F) exchange bias systems. Variations of FMR LW with the thickness and deposition order of the F and AF layers were studied, as well as their correlation with the exchange bias field and roughness of the
more » ... ghness of the sample surface. We observed much larger LW in AF/F structures compared with F/AF samples. It was found that neither the exchange bias nor surface/interface roughness in the samples could explain the difference in LW for F/AF and AF/F samples. Instead, the different underlayer microstructure influenced the grainsize, leading to different angular dispersion of magnetization and different internal stray field in F-layers, promoting a different intensity of magnon scattering and FMR damping in F/AF and AF/F samples.
doi:10.3390/magnetochemistry7050070 fatcat:qahnvibqj5as5kdhtv5ryhl6ya