Low-field microwave absorption behaviors on single layer magnetic film and exchange coupled multilayer magnetic film

•The magnetization process of the single and exchange coupled magnetic films.•The microwave absorption employed FMR and LFMA.•We examine the physical parameters such as magnetic anisotropy by VSM, FMR and LFMA.•Magnetic inhomogeneity was verified by FMR absorption peaks.

This study examined the magnetization reversal effects on low-field microwave absorption in a Fe91.6B2.5N5.9 single layered film with in-plane uniaxial magnetic anisotropy and a multi-layered film with giant magnetoresistivity using ferromagnetic resonance measurements at 9.84 GHz. Two different kinds of absorption modes were observed at near zero dc field and high dc field. The signals at high-field showed all the features of ferromagnetic resonance due to spin precession. However, the absorption signals at low-field should be associated with the switching field at unsaturated magnetic field region.