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1.
The possibility of the existence of a magnetostatic analog of Love surface elastic waves is predicted. They appear in situations
where the conditions for the existence of magnetostatic volume waves hold in the upper layer of a ferromagnetic bilayer, but
not in the lower layer.
Zh. Tekh. Fiz. 68, 85–90 (October 1998) 相似文献
2.
Effects of the resonant Bragg scattering of magnetostatic backward volume waves on the periodic structure of a conductive
meander pattern with an alternating current are analyzed theoretically and compared with experiment. It is shown that unlike
a static grating, a dynamic grating causes a frequency shift of the scattered wave. It is proposed that this phenomenon be
utilized for effective control of the intermodal conversion of magnetostatic waves.
Zh. Tekh. Fiz. 68, 105–112 (May 1998) 相似文献
3.
A. V. Vashkovskii É. G. Lokk V. I. Shcheglov 《Journal of Experimental and Theoretical Physics》1998,87(4):776-787
The propagation of zero-exchange spin waves (magnetostatic waves) is investigated in yttrium iron garnet films having a regular
stripe domain structure with almost in-plane orientation of the domain magnetization vectors. The characteristics of the waves
are studied for magnetizations of the film parallel and perpendicular to projections of the [111] crystallographic axes onto
the plane of the film. It is established, in contrast with films having the domain magnetization vectors oriented close to
the normal to the plane of the film, that both the propagation of magnetostatic waves and the variation of the parameters
of the domain structure exhibit a distinctly pronounced hysteretic character as the magnetizing field is varied. The hysteresis
of the amplitude-frequency response, equiphase, and dispersion curves of the magnetostatic waves is investigated. The authors
examine how the hysteresis of these parameters is related to the hysteresis of the domain structure. The spectrum of magnetostatic
waves is found to have an interval of wavelengths (wave numbers) that are not excited in the unsaturated film when the applied
field is close to the saturation value, and this phenomenon as well exhibits hysteresis.
Zh. éksp. Teor. Fiz. 114, 1430–1450 (October 1998) 相似文献
4.
G. A. Melkov A. A. Serga A. N. Slavin V. S. Tiberkevich A. N. Oleinik A. V. Bagada 《Journal of Experimental and Theoretical Physics》1999,89(6):1189-1199
A solution is obtained for the general problem of the nonstationary interaction of backward volume magnetostatic waves in
films of yttrium-iron garnet with local parametric pumping. In the case of a large pump region, l≫λ, where λ is the wavelength of the backward volume magnetostatic waves, the problem reduces to a system of truncated equations for
two packets of counter propagating waves. In the opposite case, l<λ, the exact problem of parametric interactions of the eigenmodes of a ferrite film (both counterpropagating and in the same
direction) is solved numerically. Both cases are studied experimentally and good qualitative and quantitative agreement is
obtained with the theory. For the first time, the reversal of a wave front and the time reversal of the shape of backward
volume magnetostatic wave pulses are observed and a change in the propagation time for the peak of the signal pulse and a
reduction in its width owing to pumping are recorded. Two operating regimes are identified for a nonstationary parametric
backward volume magnetostatic wave amplifier with local pumping, which differ in the ratio of the duration of the pump pulse
to the transit time for the wave through the local pump region, and the effect of the parametric excitation of two-dimensional
spin waves on the interaction of backward volume magnetostatic waves with a local nonstationary parametric pump is determined.
Zh. éksp. Teor. Fiz. 116, 2192–2211 (December 1999) 相似文献
5.
The nonlinear properties of exchange-free surface magnetostatic spin waves in a layered structure containing films of a ferromagnet
and a semiconductor are investigated theoretically. The stability of nonlinear surface magnetostatic waves relative to longitudinal
disturbances is investigated using the envelope evolution equation in the weak-nonlinearity approximation. It is shown that,
under certain conditions, a surface spin-wave pulse propagates in the form of an envelope soliton. Calculations are performed
for the case of an yttrium iron-garnet-indium antimonide structure.
Fiz. Tverd. Tela (St. Petersburg) 41, 1272–1275 (July 1999) 相似文献
6.
G. T. Kazakov A. V. Kozhevnikov Yu. A. Filimonov 《Journal of Experimental and Theoretical Physics》1999,88(1):174-181
This paper describes an experimental study of variations of the dispersion and damping of magnetostatic surface waves in ferrite
films, caused by three-and four-magnon interactions with parametric spin waves excited by an auxiliary surface magnetostatic
pump wave with frequency f
p. The variations in the dispersion and damping were identified, respectively, with variations Δk″ in the real part and Δk′ in the imaginary part of the wave number of the surface magnetostatic wave. The Δk″ and Δk′ values were determined from the ratio of the changes of the phase increment Δφ and the amplitude increment ΔA of the surface magnetostatic wave to the length L of the nonequilibrium section of the film, where the parametric spin waves exist. It is found that, when three-magnon decay
processes are allowed for the pump wave and the surface magnetostatic probe wave, the probe wave can substantially alter the
distribution of the parametric spin waves in the film.
Zh. éksp. Teor. Fiz. 115, 318–332 (January 1999) 相似文献
7.
A theoretical study is made of the trajectories and of the changes in magnitude and direction of the wave vectors of magnetostatic
backward surface waves with different frequencies propagating in ferrite-insulator-metal structures with different insulating
layer thicknesses and magnetized by a linearly nonuniform static field. It is shown that both forward and backward magnetostatic
surface waves (MSSWs) propagate in a waveguide channel, on one side of which MSSWs undergo mirror reflection and on the other
side of which their propagation direction is rotated, independently of the thickness of the insulator in the structure. It
is shown that when MSSWs propagate in a nonuniform field, the forward wave is converted into a backward wave and, under certain
conditions, the backward wave is converted into a forward wave. Some features of the propagation characteristics of magnetostatic
backward surface waves are determined.
Zh. Tekh. Fiz. 69, 70–77 (February 1999) 相似文献
8.
S. L. Vysotskii G. T. Kazakov Yu. A. Filimonov A. V. Maryakhin 《Technical Physics》1998,43(7):834-845
The influence of exchange coupling of layers on the propagation of magnetostatic dipole volume waves in normally and tangentially
magnetized two-layer epitaxial ferrite structures is investigated. It is shown that the indicated influence is manifested
in the form of dynamic spin pinning effects on the interlayer boundary and formation of a common dipole-exchange wave spectrum
for the entire structure. In this case, at the synchronism frequencies of the dipole and exchange waves the losses of the
dipole waves grow and anomalous segments appear in the dispersion. In films magnetized in the “hard” direction relative to
the axis of normal uniaxial surface anisotropy the magnetostatic dipole volume waves can interact resonantly with the surface
spin waves supported by the boundaries with pinned spins.
Zh. Tekh. Fiz. 68, 97–110 (July 1998) 相似文献
9.
Variations in the spectrum and damping of magnetostatic waves are observed in p-HgCr2Se4 irradiated by a strong microwave electric field. The variations depend on the magnetostatic wavenumber and the electrical
conductivity of the crystal. The results are discussed in the model of magnon heating by high-energy carriers.
Fiz. Tverd. Tela (St. Petersburg) 40, 505–507 (March 1998) 相似文献
10.
A. O. Korotkevich S. A. Nikitov 《Journal of Experimental and Theoretical Physics》1999,89(6):1114-1119
This paper explains the modulation instability of two surface magnetostatic spin waves simultaneously propagating in a ferromagnetic
film. Self-modulation of the spin waves appears when their power reaches a threshold, and this is a sign of cross-phase modulation.
The parameters of the unstable process are calculated, and the gains of the perturbation amplitudes are determined. The results
published earlier on the experimental detection of the cross-phase modulation of spin waves are explained.
Zh. éksp. Teor. Fiz. 116, 2058–2068 (December 1999) 相似文献
11.
The influence of surface-layer vortex pinning in a type-II superconductor on the propagation of surface magnetostatic waves
in a ferromagnet-superconductor structure is analyzed. The pinning is assumed to be strong enough to prevent vortex displacement
under the influence of the Lorentz force generated by the surface magnetostatic waves, so that the ground state of the superconductor
is determined by the elastic properties of the vortex lattice and by pinning. In the given model the problem reduces to the
analysis of the wave spectrum in the scattered field created by the disordered vortex surface layer. A calculation shows that
the influence of this field on the surface magnetostatic-wave spectrum is slight and, hence, degradation of the shielding
properties of the superconductor does not take place in the presence of strong vortex pinning (as opposed to the ferromagnet-ideal
superconductor structure).
Fiz. Tverd. Tela (St. Petersburg) 40, 32–35 (January 1998) 相似文献
12.
A. V. Vashkovskii É. G. Lokk V. I. Shcheglov 《Journal of Experimental and Theoretical Physics》1997,84(3):560-568
The propagation of surface and volume magnetostatic waves in unsaturated films of yttrium iron garnet is studied experimentally
for the case when the wavelength greatly exceeds the domain width, while the domain width is comparable to the film thickness.
The characteristics of these waves are examined for symmetric linear, asymmetric linear, and symmetric zigzag strip domain
structures in the films. These characteristics cannot be explained by a theory based on averaging the magnetization over all
the domains.
Zh. éksp. Teor. Fiz. 111, 1016–1031 (March 1997) 相似文献
13.
V. V. Shagaev 《Technical Physics》1998,43(10):1226-1230
Expressions for the temperature coefficients of frequency for magnetostatic waves in tangentially magnetized ferrite films
having cubic anisotropy are obtained and analyzed. It is shown that in cases where the cubic axis lies in the plane of the
film, temperature-induced changes in both the magnitude and direction of the external field can be used for thermostabilization
of the frequencies. The problem of two-frequency thermostabilization is considered. The results of experimental investigations
of the temperature characteristics of magnetization waves in a tangentially magnetized film of yttrium iron garnet with a
{100} surface are presented.
Zh. Tekh. Fiz. 68, 99–103 (October 1998) 相似文献
14.
The field distribution of magnetostatic surface and volume waves as they propagate at an arbitrary angle to a constant field
in a tangentially magnetized ferromagnetic slab (Damon-Eschbach waves) is investigated. Snapshots of the magnetic field lines
of the wave are constructed. The variation of the magnetic field distribution with thickness is qualitatively identified for
a volume wave as it propagates at an angle equal to the cutoff angle of the surface wave, as a result of which the sinusoidal
profile of the wave over thickness almost discontinuously acquires an additional phase difference.
Zh. Tekh. Fiz. 69, 82–86 (January 1999) 相似文献
15.
Magnetostatic surface waves with fixed frequency and wave vector are predicted to exist in a ferromagnet with an inhomogeneity
of the magnetic anisotropy such that the spectral function has a turning point on the surface. This result is most important
for the case when an external magnetic field magnetizes the ferromagnet perpendicular to its surface. The frequency of the
surface wave is determined by the frequency of the magnetostatic volume wave at the surface of the ferromagnet, and the wave
vector is determined by the surface values of the local magnetic anisotropy field and its derivative.
Zh. Tekh. Fiz. 68, 118–123 (June 1998) 相似文献
16.
In addition to the general dispersion equation for surface-localized magnetic polaritons and magnetostatic waves, which propagate in the system antiferromagnetic superlattice-antiferromagnet, we derive a simplified result for the long-wavelength limit λ?L (L is the period of superlattice) when the superlattice is found to behave like an anisotropic bulk medium (effective-medium approach). The dispersion curves and frequency region of the existence of the surface magnetic polaritons and magnetostatic waves are presented numerically for several values of the external magnetic field and for different antiferromagnetic materials. 相似文献
17.
We present a detailed study of the dispersion properties of surface magnetostatic waves in layered structures of ferrite and high temperature superconductor (HTSC) layers. We solve the propagation problem for the surface magnetostatic waves under a quasistatic approximation, and obtain the dispersion relation. We present an analysis of this dispersion near the phase transition temperature in the HTSC layer. The calculations show that when the HTSC material transforms to the superconducting state the dispersion properties of the magnetostatic waves changes suddenly: the damping decreases by 4–10 dB and the phase velocity increases by a factor of 2–4. These results support experiments which have been performed, in which surface magnetostatic waves have been studied in a YIG film with gallium impurities and a YBaCuO film on a lithium niobate substrate.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 50–55, March, 1995. 相似文献
18.
The four-magnon instability of magnetostatic surface waves (MSSWs) in yttrium iron garnet epitaxial films is investigated
experimentally. It is shown that four-magnon instability for MSSWs with wave numbers 30–600 cm−1 is a decay instability and develops for values of the wave magnetization close to the threshold level for second-order parametric
instability of a homogeneous transverse pump wave. When the supercriticality of the MSSW power is 15–20 dB, the generated
parametric spin waves themselves become unstable with respect to the four-magnon interaction, so that kinetic instability
develops in the film. It is shown that the pump signal transmitted through the signal and the length of the “nonlinear” part
of the film, where a MSSW is capable of exciting parametric spin waves, increase as the pump power is increased.
Fiz. Tverd. Tela (St. Petersburg) 38, 330–338 (February 1997) 相似文献
19.
V. V. Shagaev 《Physics of the Solid State》1998,40(11):1892-1895
Analytical expressions are derived for the derivatives of the frequencies of magnetostatic waves with respect to the external
magnetic field in anisotropic ferromagnetic films. Films having cubic anisotropy and 〈100〉, 〈110〉, and 〈111〉 surfaces are
analyzed in detail. The frequency-field relations are used in an experimental determination of the temperature coefficients
of the cubic anisotropy field and the saturation magnetization in an yttrium iron garnet film.
Fiz. Tverd. Tela (St. Petersburg) 40, 2089–2092 (November 1998) 相似文献
20.
Bragg interaction of surface magnetostatic waves with a periodic granular high-temperature superconducting structure is studied. A dispersion equation for coupled waves describing the characteristics of surface magnetostatic waves is derived. Resonance wave absorption near the critical temperature is revealed. The magnetostatic wave reflection coefficients of semi-infinite and finite periodic high-temperature superconducting structures are calculated. The results obtained can be used in designing tunable frequency selectors and transient bolometric photodetectors. 相似文献