Explore the vast range of titles available.

AbstractThe effect magnetic anisotropy has on oscillations of the vector of magnetization in magnetic films under the influence of an alternating magnetic field is studied as functions of the time, frequency, and magnetic field strength. It is shown that the reorientation of the vector of magnetization between two mutually perpendicular axes of easy magnetization with magnetic anisotropy in magnetic films can be accompanied by nonlinear and bifurcation oscillations.

AbstractA numerical model is created of the magnetoelastic dynamics of a three-layer ferromagnetic structure excited by a microwave magnetic field. Portraits are constructed of the precession of magnetic oscillations. Values of the layer parameters and field amplitudes are determined for the maximum transfer of energy from the magnetic subsystem to the elastic subsystem of the three-layer structure.

AbstractMicrowave magnetic impedance spectra are obtained for \\([(Co_0.52Fe_0.45B_0.2)_x + (SiO_2)_y]\\) (x = 0.46–0.88) films in a DC magnetic field of 0‒0.7 T. The modulus of microwave impedance in films with x = 0.76 is found to fall by as much as 6% upon magnetization. The maximum negative microwave magnetic impedance of the films is established along with its shift from 2.2 to 0.4 GHz as x rises. A striped magnetic structure with oppositely directed magnetizations of neighboring stripes is observed.

AbstractA study is performed of the second-order precession of the vector of magnetization in a two-layer magnetically coupled structure. Numerical solutions are obtained for the dynamics of the magnetic subsystem of a two-layer film. Parametric portraits of the vector of magnetization’s motions are constructed for the effect external asymmetric fields and internal fields of anisotropy have on the dynamics of magnetization. A correlation is established between interlayer coupling and the character of parametric magnetization portraits.

AbstractA study is performed of oscillations of magnetization and elastic oscillations in a YIG film. Parametric portraits are presented for oscillations of the vector of magnetization, time sweeps of elastic oscillations, and their amplitude–frequency characteristics at different depths of modulation and strengths of an ac magnetic field. The dependences on the modulation depth and the amplitude of the alternating field are also given. The conditions for effective detection of external magnetic field oscillations are determined.

AbstractResults are presented from studying the magnetic resonance properties of metal–dielectric (CoFeB + SiO2) and metal–carbon (CoFeB + C) composite films. The effect the concentrations of the magnetic metal, dielectric, and carbon phases of the composite films on the characteristics of ferromagnetic resonance is analyzed.

The authors study conditions for the magnetization reorientation of nickel nanofilms with a toothed stripe structure when acoustic pulses of Gaussian shape pass through them. The behavior of such films in a constant magnetic field is studied and hysteresis loops are constructed, depending on the angle of the field’s application. Modeling is done using the MuMax3 software package. Results can be used in developing advanced compact and energy-efficient magnetic recording devices.

Composite films of A series of compositions [(Co 0.45 Fe 0.45 Zr 0.10 ) x + (Al 2 O 3 ) (1 – x)/5 ], x = 0.25-0.66 and B series of compositions [(Co 0.86 Nb 0.12 Ta 0.02 ) x +(SiO 2 ) (1–x)/3 ], x=0.14-0.78 were investigated. Images of magnetic micro- and nanostructures of the A, B series composite films were obtained. At small x≤0.3, we observe a chaotic spread of magneto-metallic nanoparticles in a dielectric matrix. In the range 0.300.6, we observe a chaotic scattering of dielectric nanoparticles in a magneto-metallic matrix. We obtained dependences of the specific impedance modulus of composite metal-dielectric films on the current frequency and on the concentration of the metal alloy of A, B series films. The analysis of the spectra showed that films in the frequency range from 0.1 to 3 GHz could exhibit three behaviors of the impedance spectra. For films with x up to the percolation threshold, a capacitive character is observed. The impedance in the field of percolation processes is capacitive, inductive or mixed character. After the percolation threshold, the impedance has an inductive character, and the frequency-dependent character of the magnetic permeability of the films can make a large contribution to the behavior of the spectra.

AbstractA review of modern lines of research in the field of ultrafast magnetoacoustics is presented. Effects of interaction of ultrashort (picosecond) acoustic pulses with a magnetic subsystem of magnetic films and particles, as well as interaction of surface acoustic waves excited by femtosecond laser pulses with magnetic nanostructures, are considered. A separate direction of modern ultrafast magnetoacoustics involves interaction of surface acoustic waves with a magnetic subsystem in planar nanostructures. The conditions of this interaction for nonuniform magnetization modes are unclear and effects of interaction of surface acoustic waves with metasurfaces have been poorly studied. A promising method of excitation and detection of surface magnetoelastic waves in metal films and planar nanostructures is to apply the “transient grating” technique, which makes it possible to use modern femtosecond lasers and has very good temporal resolution. The main results of experiments on excitation of magnetoelastic modes in films and planar periodic nanostructures upon ultrafast laser excitation are discussed and the models of magnetoelastic nonlinear dynamics obtained by researchers all over the world over the last decade have been analyzed.

The micro- and nanostructure of 328–772-nm-thick amorphous granulated (Co45Fe45Zr10)x(ZrO)1 – x (0.27 < x < 0.61) composite films deposited in argon on a lavsan substrate has been examined using atomic force microscopy, magnetic force microscopy, and scanning electron microscopy. It has been shown that the mean sizes of the grain and the metallic phase content govern the conductive and reflective properties of the films in the microwave range.