Control of the susceptibility spectrum in polycrystalline ferrite materials and frequency threshold of the losses

In ferrites the resonance character of the dispersion of the domain-wall movement can be systematically obtained by a specific preparation technology. This resonance character could be attributed to a discontinuity of the walls. The main practical interest of such materials is the possibility to shift the dispersion and the losses threshold to higher frequencies, for a given susceptibility, in comparison with a standard material having the same composition. A material capable of working in the VHF range is presented.