Stimulated Raman backscattering of a focused pumping beam: numerical experiment
Stimulated Raman backscattering of a focused pumping beam: numerical experiment
S.Yu. Nikitin, D.A. Sivashov
Approximate dynamic equations for light wave power have been derived which describe the process of stimulated Raman backscattering with allowance for the inertia of molecular vibrations and the focusing of the pumping beam. The numerical calculation results agree well with experimental data on stimulated Raman scattering in hydrogen.
Show AbstractThe Lorentz magnetoresistance of disordered alloys in the coherent-potential approximation
The Lorentz magnetoresistance of disordered alloys in the coherent-potential approximation
A.V. Vedyaev, A.B. Granovskii, D.Kh. Imamnazarov, I.Kh. Khalilov
The transverse Lorentz magnetoresistance of a one-zone model of a disordered crystalline alloy has been calculated within the framework of the coherent-potential approximation for the case of arbitrary scattering intensity. When the scattering is strong and the law of dispersion is isotropic, the magnetoresistance is proportional to the damping of the electronic states at the Fermi level.
Show AbstractSpin damping of magnetoelastic waves in cubic ferromagnetics
Spin damping of magnetoelastic waves in cubic ferromagnetics
0.Yu. Belyaeva, S.N. Karpachev
A new method for estimating spin relaxation times in magnetic materials by ultrasound damping is considered. A description is given of a phenomenological theory of the relaxation mechanism of sound damping in a single-domain perfect crystal with consideration for a nonhomogeneous internal field. Numerical estimates of spin relaxation times in a Mn-Zn spinel single crystal are presented that use data on damping of a 30-MHz transverse wave. A possibility of separating the spin-spin and the spin-lattice relaxaton times is discussed.
Show AbstractThe indeterminacy of the output stationary characteristics of a double-passage optical system with a nonlinear gyrotropic medium and a semitransparent mirror
The indeterminacy of the output stationary characteristics of a double-passage optical system with a nonlinear gyrotropic medium and a semitransparent mirror
A.A. Golubkov, V.A. Makarov
The polarization parameters of stationary states of the field in a nonlinear medium have been studied. These parameters are found to change only slightly when deviations of the refractive index of the mirror from unity are small.
Show AbstractВладимир Александрович Красильников (к 80-летию со дня рождения)
Владимир Александрович Красильников (к 80-летию со дня рождения)
В.Б. Брагинский, В.А. Буров, Л.К. Зарембо, Н.И. Коротеев, В.В. Крылов, В.И. Павлов, О.В. Руденко, И.Ю. Солодов, А.П. Сухоруков
14 сентября 1992 г. профессору Владимиру Александровичу Красильникову исполняется 80 лет.
Show AbstractThe theory of transversely inhomogeneous heavy-current beam-plasma amplifier under conditions of collective Cerenkov effect
The theory of transversely inhomogeneous heavy-current beam-plasma amplifier under conditions of collective Cerenkov effect
M.V. Kuzelev, V.A. Panin
The paper is concerned with both linear and nonlinear theories of amplifying electromagnetic plasma waves in a transversely inhomogeneous beam-plasma system of a general form under conditions of the collective Cerenkov effect. The optimum length and efficiency of amplification, as well as the output electromagnetic radiation power have been calculated analytically and numerically.
Show AbstractThe effect of transverse inhomogeneity of the pumping field on electron motion in nonadiabatic magnetic undulators with guiding magnetic field
The effect of transverse inhomogeneity of the pumping field on electron motion in nonadiabatic magnetic undulators with guiding magnetic field
V.A. Kubarev
Setting up optimal radiation regimes of helical relativistic electron beams requires a definite value of the electron pitch factor. The presence of a transverse inhomogeneity of the pumping field in real undulators leads to the following two main consequences: a widening of the nonlinear resonance and a drift of the guiding centers of the particles. A theory of these effects is developed for symmetric and asymmetric undulators with a homogeneous guiding magnetic field.
Show AbstractCharacteristics of intermode striction coupling in spherical electroacoustic resonators
Characteristics of intermode striction coupling in spherical electroacoustic resonators
G.V. Belokopytov, N.P. Pushechkin, V.N. Semenenko
Integrated characteristics of the intermode striction interaction of electromagnetic and acoustic oscillations in spherical resonators have been studied. Selection rules are established and integrated striction interaction characteristics are calculated with consideration for the vector character of the fields and the electrostriction tensor anisotropy. There was good agreement between the calculated and experimental data on striction parametric excitation of radial elastic oscillations by UHF pumping in potassium tantalate dielectric resonators.
Show AbstractPolarization effects in light propagation through an acoustic field in an isotropic medium
Polarization effects in light propagation through an acoustic field in an isotropic medium
A.I. Balakshii, D.A. Khasan
The variation of light polarization in the process of Bragg's acoustooptic interaction has been investigated theoretically. It is shown that in the propagation of linearly polarized light through an acoustic field excited in an isotropic medium the light radiation becomes elliptically polarized. By varying the ultrasound intensity or frequency it is possible to control the polarization state. The effect of polarization nonreciprocity has also been studied for two light waves propagating through an acoustic field in the opposite directions.
Show AbstractThe effect of variation of the refractive index and thickness of layers in thin-layer interference filters on their optical parameters
The effect of variation of the refractive index and thickness of layers in thin-layer interference filters on their optical parameters
A.V. Kosar', E.V. Putrina
Changes in the refractive index of a medium to be matched and in the matching wavelength upon variation of the refractive indices and thicknesses of layers in thin-layer interference filters (TIF) were studied theoretically (the optical thickness of the layers is smaller than a quarter wavelength) for TIF with two and three layers in a period. New properties of such filters were discovered, in particular, the invariance of these changes with respect to the number of periods when the refractive indices of the layers vary. Simple analytical expressions were obtained that allow an adequate determination of the shift in the parameters under consideration. A computer-aided numerical analysis confirmed the theoretical predictions.
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