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This paper examines the specific electric resistance, magnetization, porosity, demagnetizing fields, and relaxation magnetization frequencies in composite (Co 45 Fe 45 Zr 10 ) X (Al 2 O 3 ) 100− X films. A strong correlation between the ferromagnetic resonances (FMR) line width, the relaxation frequency, and specific resistance are observed. The FMR line shape for films with a small percentage of the metal phase transforms from a resonant line shape to a relaxation line shape as the temperature decreases or the film is annealed. This transition is connected to the changes in the metal–dielectric boundary properties.

The dynamics of the magnetization in the ferrite film close to the nonlinear magnetoacoustic resonance (MAR) for different magnitudes of the magnetic dissipation parameter is investigated. The interval of the magnetic dissipation parameter magnitudes, in which the nonlinear relaxation and strong damping of the magnetization is observed, is defined. The regime of the magnetoelastic autooscillations is observed if there is some detuning of the acoustic eigenfrequency from the MAR frequency in certain intervals of values of the alternating field amplitude during its action.

The nonlinear dynamics of an ensemble of single-domain interacting particles upon excitation by radio-frequency pulses of a magnetic field is investigated. Reorientation of magnetic moments of ensemble particles under the effect of the pulses of the radio-frequency field is observed. The effect of varying the magnetic structure on the frequency dependences of susceptibility is studied. Temporal characteristics of precession in separate particles under the conditions of an orientation transition are considered.

Amorphous silver, copper, gold, and iron films with a thickness of 6–60 nm have been grown on a polymer substrate by the method of vacuum deposition. The dependences of the specific conductivity and the microwave reflection coefficient on the film thickness are obtained and a relation between these values is established.

Amorphous silver, copper, gold, and iron films of a thickness between 6 and 350 nm are grown on polymeric substrates by vacuum evaporation. The nanostructure of the films is investigated. The dependence of the conductivity on the film thickness is obtained, and a correlation between the surface morphology and the conductivity is established.

The composite films were investigated by AFM methods before and after annealing. Topographic and phase-contrast AFM images of the composite films at different annealing temperature were obtained. The separate metal granules and larger-scale labyrinth-like formations were described. These formations appear by the process of the film growth, also by film annealing. Strong changes of the structural properties of the films are observed after the percolation transition. The significant changes of the structural properties are connected with nanostructural transformations in the metal granules topology and presence of metal crystal phase.

The occurrence of translational motion in the domain system in a ferrite plate under harmonic parametric action is investigated. The domain dynamics is described on the basis of the numerical solution of differential equations for a system of connected oscillators. Transition scenarios from oscillatory to translational motion are described, depending on the changes in the nonlinearity constant and damping parameter for various numbers of oscillators.

The technique of X-ray reflectometry used for studying the sizes of metallic and dielectric inclusions in nanocomposite films (Fe45Co45Zr10) · (Al2O3)100−x depending on their composition is described. The size of isolated metallic inclusions increases with an increase in metallic phase concentration and reaches its maximum in the region of the percolation threshold. Above this threshold, metallic inclusions merge, thus forming a matrix with dielectric inclusions.

The work is devoted to the research of the magnetic and relaxation properties of metal-dielectric (composite) films and revealing their relationship with the nanostructure characteristics. The nanosize of ferromagnetic particles in the composite films results in unusual magnetic properties including an abnormal magnetization relaxation. Correlation of the magnetic relaxation frequencies and specific electric resistance with the nanostructure characteristics are discovered. The FMR line shape for films with a small percentage of the metal phase transforms from a resonant line shape to a relaxation line shape if the film is annealed. This transition is connected to the changes in the array of metal and dielectric particles and its boundary properties. The significant changes in the shape of the FMR spectra lines are connected to nanostructural transformations in the ferromagnetic granules topology and distance between the granules.

Nano- and microstructure of {(Co4-Fe4-Zr0.7)x+(A12O3)1-x} (Al series) and {(Co1-Nb0.2-Ta0.05)x+(SiO2)1-x} (A2 series) films was investigated by atomic force microscopy. The distributions of the metallic granules effective size by various concentrations of the metal phase were obtained. Microwave magnetic characteristics of composite films in respect of obtained distributions were calculated.

This work is devoted to the research of influence of annealing to ferromagnetic resonance (FMR) properties of films of the A, B series with the compositions of (Co45-Fe45-Zr10)x(Al2O3)y, multilayer films of the D series with compositions {[(Co45-Fe45-Zr10)x(Al2O3)y]-[alpha-Si]}120 and revealing their relationship with the nanostructure characteristics. The films were obtained in an argon atmosphere (the A, D series) and with addition of oxygen (the B series). All samples were deposited on substrates by the ion-beam sputtering method and were annealed. The resonant fields and width of ferromagnetic resonance (FMR) line were measured before and after annealing. The changes in the FMR field and width of the line at varying temperatures of annealing for the composite and multilayer films are analyzed in the work. The character of changes in the structural characteristics of films at different annealing temperatures is determined.

Composite-semiconductor and composite-dielectric multilayer films were obtained by the ion beam sputtering method in the argon and hydrogen atmospheres with compositions: {[(Co45-Fe45-Zr10)x(Al2O3)y]-[α-Si]}120, {[(Co45-Ta45-Nb10)x(SiO2)y]-[SiO2]}56, {[(Co45-Fe45-Zr10)x(Al2O3)y]-[α-Si:H]}120. The images of surface relief and distribution of the dc current on composite layer surface were obtained with using of atomic force microscopy (AFM). The dependencies of specific electric resistance, ferromagnetic resonance (FMR) fields and width of line on metal (magnetic) phase concentration x and nanolayers thickness of multilayer films were obtained. The characteristics of FMR depend on magnetic interaction among magnetic granules in the composite layers and between the layers. These characteristics depend on the thickness of composite and dielectric or semiconductor nanolayers. The dependences of electric microwave losses on the x and alternating field frequency were investigated.

An equation in the Gilbert form that describes the motion of the magnetization vector in intense high-frequency magnetic fields is solved numerically. The solution obtained is used to study switching of the magnetization of a single-domain ferromagnetic particle that has the shape of an ellipsoid of revolution and possesses cubic anisotropy from the position parallel to an easy axis to the position normal to this axis. The ranges of amplitudes and frequencies of the magnetic field where magnetization switching is observed are determined. An expression for the response of an ensemble of variously oriented particles is derived. It is shown that a particle ensemble generated by an rf field may serve as a data carrier on which information is written and read out by means of nonlinear and linear ferromagnetic resonances.