抄録
Polycrystalline Li-Zn ferrites were prepared by the ceramic sintering method, and their complex permeability spectra were measured. The low-frequency permeability decreased with an increase in the Li-ferrite fraction. However, the natural resonance frequency shifted higher when the fraction of Li-ferrite was increased. According to our previous model, the complex permeability spectra were numerically separated into spin rotation and domain wall motion contributions. For the spin rotational component, which played an important role in the high frequency region, the static spin susceptibility decreased and the spin resonance frequency shifted higher with an increase in the Li-ferrite fraction. The product values of the static spin susceptibility and the spin resonance frequency, corresponding to the Snoek's product value, took a maximum value at a certain fraction of Li-ferrite. This was reflected to the performance of the single layered electromagnetic wave absorber using the polycrystalline ferrites.
