SYNTHESIS OF NANOSCALED MAGNETIC MATERIALS ON THE BASIS OF OXIDE SYSTEMS AND MANUFACTURING OF NON-RECIPROCAL COMPOSITE ELEMENTS BASED ON THEM

Abstract

Nanoscaled particles of nickel-zinc ferrites solid solutions were synthesized by the method of precipitation from aqueous solutions, as initial reagents were used nitrates solutions, namely Fe(NO3)3, Ni(NO3)2 and Zn(NO3)3. Cylindrical composite resonant elements in a form of systems “high-Q non-magnetic dielectric – magnetic film” were manufactured using synthesized particles. As a non-magnetic dielectric was used barium tetratitanate BaTi4O9 with a doping of ZnO. For this the film-forming suspension consisted of synthesized ferrite particles and photopolymer was prepared. The suspension was applied on the end face of the dielectric resonator and polymerized by the UV radiation. Magnetic field of electromagnet was applied to the composite resonators during the magnetic film polymerization process (parallel or normal to the resonators axis).
 Absorption spectra of composite resonators in the waveguide measuring cell under influence of an external magnetic field were obtained. Spectra confirm the opportunity to control the resonance frequency of the composite structure and energy absorption in it using the external permanent magnetic field. The tuning of composite resonators parameters was more efficient for the resonators with the film polymerized in the parallel to the resonator axis field. For the frequency shift and electromagnetic isolation were obtained the values of 71 MHz and 53 dB respectively but with a high “straight” energy losses in the area of ferromagnetic resonance. So, the measuring cell with the composite resonator located in it was simulated using an Ansys HFSS software. Respective absorption spectra were obtained. It is shown that it is possible to manufacture composite resonators with a needed for the practical applications characteristics level (reverse losses were 34 dB, straight losses were 0.8 dB) and a tuning ability for the development of superheterodyne transmitters, dynamic filters for microwave technics, microwave valves, etc.