Magnetic imaging in thin magnetic films by local spectrometer of ferromagnetic resonance

The automatized scanning spectrometer of ferromagnetic resonance has been designed for measuring a distribution of in-plane magnetic anisotropy, effective saturation magnetization, coercivity, and other performances across the area of thin magnetic films (TMFs) in a monodomain state. The spectrometer is supplied with a set of plug-in measuring heads overlapping frequency band 0.1 ÷ 6.0 GHz. The degree of locality of measurements in the range 0.3 ÷ 2.5 mm is defined by the size of the measuring hole in the microstrip resonator built in the head. The signal-to-noise ratio of the heads is not less than 10 for permalloy film of 100-Å thickness when the locality of measurements is about 1 mm, and it can be increased considerably in the signal accumulation mode. Magnetic imaging is demonstrated with an example of purposely-stressed TMFs.