共查询到20条相似文献,搜索用时 31 毫秒
1.
A. V. Drozdovskii M. A. Cherkasskii A. B. Ustinov N. G. Kovshikov B. A. Kalinikos 《JETP Letters》2010,91(1):16-20
The formation of light envelope solitons has been experimentally observed under the pulsed excitation and propagation of radio-frequency spin-wave packets in a magnon crystal, a periodic magnetic film structure. The magnon crystal has been fabricated from a thin single-crystal yttrium iron garnet (YIG) film. The envelope solitons have been excited at frequencies corresponding to the edges of the Bragg-resonance-induced band gaps of the spin-wave spectrum of the magnon crystal. A theoretical explanation of the observed phenomenon has been proposed with the use of the numerical simulation of the formation of solitons based on the nonlinear Schrödinger equation. 相似文献
2.
It has been shown that the number of high-intensity spin-wave modes in the spin-wave resonance spectrum of films with a uniform gradient of the effective anisotropy field depends on the thickness of the film and on the exchange stiffness. It has been established that there is a “critical” thickness of the film which depends on the exchange stiffness and the anisotropy field gradient. When the thickness of the film is less than the “critical” value, only one high-intensity mode is excited in the resonance absorption spectrum. 相似文献
3.
A. B. Rinkevich D. V. Perov V. O. Vas’kovskii V. N. Lepalovskii 《Technical Physics》2009,54(9):1339-1349
Penetration of millimeter electromagnetic waves through permalloy films under magnetic resonance conditions is studied experimentally
and theoretically. Measurements are taken on film samples from 40 to 200 nm in thickness in a frequency range from 26 to 38
GHz. Magnetic resonance, antiresonance, and spin-wave resonance are observed. The resonance spectrum is reconstructed. The
Gilbert damping constant is determined for a series of films. It is shown that the damping constant decreases upon an increase
in the film thickness. The resonance line profile is calculated, and the dependences of resonance line amplitude and width
on experimental conditions and material parameters of the film are determined. 相似文献
4.
The formation of quasi-2D nonlinear spin-wave eigenmodes in longitudinally magnetized stripes of a ferrimagnetic film, the so-called guided spin-wave bullets, was experimentally observed by using time- and space-resolved Brillouin light scattering spectroscopy and confirmed by numerical simulation. They represent stable spin-wave packets propagating along a waveguide structure, for which both transversal instability and interaction with the side edges of the waveguide are important. The experiments and the numerical simulation of the evolution of the spin-wave excitations show that the shape of the formed packets and their behavior are strongly influenced by the confinement conditions. The discovery of these modes demonstrates the existence of quasistable nonlinear solutions in the transition regime between one-dimensional and two-dimensional wave packet propagation. 相似文献
5.
Sakharov V. K. Khivintsev Y. V. Dudko G. M. Vysotskii S. L. Filimonov Y. A. 《Physics of the Solid State》2019,61(9):1602-1608
Physics of the Solid State - In this paper, we study the features of the spin-wave excitation spectrum in a YIG film with a thickness of 0.4 μm and a magnetization of 1.1 kG corrugated due to... 相似文献
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7.
The two-dimensional square lattice mixed-spin anisotropic Heisenberg ferromagnet with a transverse magnetic field is studied by means of the double-time Green's function. The analytic expressions of the critical temperature, the high-temperature zero-field susceptibilities, the spin-wave velocity, spin-wave stiffness and spin-wave gap are obtained. The phase diagrams in which the critical temperature, the reorientation temperature and the reorientation magnetic field are shown as a function of single-ion anisotropic parameter are discussed. 相似文献
8.
N. K. Dan’shin V. S. Dellalov A. I. Linnik V. F. Shkar’ 《Physics of the Solid State》1999,41(8):1329-1332
Magnetic resonances are investigated in bilayer Bi-substituted iron garnet films, one layer of which possesses easy-axis and
the other easy-plane anisotropy. The behavior of resonances as a function of film thickness, temperature, and annealing is
studied. It is shown experimentally that the resonance absorption lines observed in such a nonuniform structure in an external
magnetic field oriented perpendicular to the film plane correspond to ferromagnetic (FMR) and spin-wave (SWR) resonances.
In addition, the SWR series is excited in the most nonuniform part of the film. A qualitative model explaining the experimental
data and making it possible to obtain experimentally the profile of the effective-magnetic-anisotropy field throughout the
thickness of the film is proposed.
Fiz. Tverd. Tela (St. Petersburg) 41, 1452–1455 (August 1999) 相似文献
9.
The formation and propagation of light and dark microwave spin-wave envelope solitons in a periodic magnetic film structure have been observed. The periodic structure was manufactured on the basis of the single-crystal film of iron-yttrium garnet and a lattice of copper strips placed on the surface of the film perpendicularly to the propagation direction of carrying spin waves. The solitons are generated at frequencies corresponding to the band gap in the spectrum of the spin waves of the periodic structure, which is due to the first Bragg resonance. 相似文献
10.
A. V. Filippov 《Journal of Experimental and Theoretical Physics》2016,122(4):716-721
The factors affecting the slope of the dispersion curve of the spin-wave resonance spectrum in multilayer films are determined. It is shown that an increase in the slope of the curve for the transverse orientation of the constant magnetic field relative to the film upon an increase in frequency is due to enhancement of dynamic as well as dissipative mechanisms of spin pinning. It is found that an increase in the damping parameter increases the degree of spin pinning in the case when the pinning layer is a reactive medium for spin oscillations and can decrease the degree of pinning when it is a dispersive medium. The conditions ensuring a higher degree of accuracy in determining the exchange interaction constant from the spin-wave resonance spectrum in multilayer films are determined. 相似文献
11.
M. Jirsa 《Czechoslovak Journal of Physics》1985,35(11):1309-1320
The influence of various combinations of the uniaxial surface anisotropy constantsK
s1 andK
s2 on the angular dependence of the standing spin-wave resonance (SSWR) spectrum is studied for an isotropic insulator film with asymmetrically pinned spins. It is shown that the (K
s1,K
s2)-plane can be divided into zones in which the angular dependence of the SSWR spectrum has different characteristic features. These features are studied in detail.Dedicated to Academician Vladimír Hajko on the occasion of his 65th birthday. 相似文献
12.
We show both theoretically and experimentally that a collapsing (2+1)-dimensional wave packet in a medium with cubic nonlinearity and a two-dimensional dispersion of an order higher than parabolic irradiates untrapped dispersive waves. The studies are performed for a spin-wave bullet propagating in an in-plane magnetized ferrimagnetic film. An induced uniaxial anisotropy in such a medium leads to the formation of narrow spin-wave caustic beams whose angles to the bullet's propagation direction are modified by the motion of the source. 相似文献
13.
The manifestation of fractals in soliton dynamics has been observed for the first time. The experiment utilized self-generated spin-wave envelope solitons in a magnetic film based active feedback ring. At high ring gain, the soliton that circulates in the ring breathes in a fractal pattern. The corresponding power frequency spectrum shows a comb structure, with each peak in the comb having its own comb, and so on, to finer and finer scales. 相似文献
14.
The imaginary part of the magnetic susceptibility determining the position, amplitude, and width of damped bulk and surface spin-wave eigenmodes in the spin system of a thin film magnetized in the film plane along the uniaxial bulk and surface anisotropy axis is analyzed numerically for various values of the degree of surface spin pinning. The presence of damping and the finiteness and asymmetry of the degree of surface spin pinning are shown to cause significant changes in the spin-wave resonance spectrum. 相似文献
15.
Yu. A. Mamalui Yu. A. Siryuk 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(5):632-634
The temperature behavior of the domain structure in a two-layer ferrite-garnet film with one of the layers having a compensation point T c , as well as in single-layer witness films, has been experimentally investigated. It is shown that the rare earth sublattice affects phase transitions in the domain structure of a two-layer film. The phase transitions observed were explained in terms of the concept of magnetostatic pressure in the domain structure. 相似文献
16.
The nanorelief of orienting surfaces in a nematic layer is studied experimentally. The initial inclination angle of the director and the phase retardation of light in the crystal are determined, and the director reorientation dynamics in the crystal under SB deformation in an electric field is analyzed. It is shown that a thin layer of amorphous hydrogenated carbon (a-C: H) deposited on a GeO monoxide layer with an anisotropic nanorelief produced by the inclined deposition method smoothens the surface topography without changing the surface structure. Modification of the structure and physicochemical properties of the GeO surface alters the conditions of the anisotropic-elastic interaction at the interface with the liquid crystal, as evidenced by an increase in the S-effect threshold and a decrease in the initial inclination of the director from 22° (on the GeO surface) to 0–6°. Strong influence of the surface nanostructure on the dynamics of the director reorientation in the electric field and on the phase modulation of light is experimentally demonstrated. It is shown that the phase retardation of light in the GeO layer covered by an a-C: H film is twice as large as in the layer of the same thickness with a virgin surface. 相似文献
17.
The emergence of the self-modulation instability of monochromatic microwave spin waves excited in a periodic magnetic film structure, a magnonic crystal, has been observed. The magnonic crystal was fabricated by chemically etching the surface a single-crystal yttrium-iron garnet film. The self-modulation instability has been observed at the frequencies corresponding to the band gaps of the spin-wave spectrum of the magnonic crystal caused by Bragg resonances. Above a certain threshold value of the input microwave signal, the time profile of the output pulses corresponds to envelope solitons. 相似文献
18.
A. M. Zyuzin S. N. Sabaev V. V. Radaikin A. V. Kulyapin 《Physics of the Solid State》2002,44(5):932-937
Mechanisms leading to anisotropy of dispersion curves of the spin-wave resonance spectrum in magnetic multilayer films are investigated experimentally and theoretically. One of the reasons for the considerable increase in the dispersion-curve slope for the static magnetic field directions intermediate between the parallel and normal ones in relation to the film plane is shown to be connected to the alteration of the equilibrium orientation of magnetization. This factor (in addition to the dominant dissipative mechanism of the spin pinning and to the reactive or dispersive properties of a layer with strong damping) is established to affect the wavenumbers of standing spin waves and cause a difference between the dispersion curves for normal and parallel orientations of the dc magnetic field. 相似文献
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20.
A. V. Sadovnikov S. A. Odintsov E. N. Beginin A. A. Grachev V. A. Gubanov S. E. Sheshukova Yu. P. Sharaevskii S. A. Nikitov 《JETP Letters》2018,107(1):25-29
The spin-wave dynamics in the system of lateral magnetic microstructures have been studied experimentally and numerically. Regimes of the propagation of coupled spin waves have been investigated by Brillouin spectroscopy measurement and numerical experiment. A phenomenological model has been proposed to describe the properties of spin waves in a lateral structure. It has been shown that the length of the coupling between spin waves can be governed by varying the power of the signal. The results can be used to fabricate magnetic waveguides of spin-wave demultiplexers, power splitters, and microwave couplers based on the lateral system. 相似文献