Theory of X-ray diffraction in solid state superlattices
Theory of X-ray diffraction in solid state superlattices
A.V. Kolpakov, I.R. Prudnikov
The problem of Bragg's X-ray diffraction (XRD) in one-dimensional superlattices (SL) has been studied in detail. A comprehensive review of the publications devoted to this problem is given. A solution of the XRD problem for doped and composite SL with a random modulation law has been obtained in the general form within the kinematic approximation. The effect of the type of a modulating function upon the diffraction spectrum is discussed. In order to solve the problem of the dynamic XRD, we have introduced the concept of the eigen-solutions of the Takagi equations. This has enabled us to use effectively, when studying the problem at hand, the methods of perturbation theory and of slowly varyng amplitudes and to give a thorough analysis of the approximate solutions obtained. Based on the recurrent relations of a new type, the general solution of the problem of XRD in SL is obtained and discussed in various approximations. The exact solution is given for the model of the dynamic XRD in SL with the rectangular modulation. The relation is established between the results obtained with the help of the above methods and those obtained by other authors. The absorption effect is briefly discussed.
Show AbstractTwo-dimensional electron gas in a strong magnetic field (quantum limit)
Two-dimensional electron gas in a strong magnetic field (quantum limit)
V.R. Khalilov
A multi-particle wave function for the ground state of magnetized two-dimensional electrons is proposed. The pattern of electron states it gives corresponds to the Wigner two-dimensional lattice. It is also shown that the quantized Hall effect results from spontaneous violation of the translational symmetry of a respective quantum system.
Show AbstractThe NUT solution to the equations of relativistic gravitation theory
The NUT solution to the equations of relativistic gravitation theory
J.E. Pinzon Q., P.V. Karabut
The NUT solution to the equations of relativistic gravitation theory is studied. It is shown that the presence of the NUT parameter in the metric of the effective Riemann space results in the appearance of gravitational fields of nonphysical character.
Show AbstractAn investigation of correlation properties of many-particle systems within the framework of the two-particle density functional method
An investigation of correlation properties of many-particle systems within the framework of the two-particle density functional method
0.S. Erkovich$^1$, V.V. Komarov$^1$, A.M. Popova$^1$, 0. Melsheimer$^2$, H. Neumann$^2$
The effect of pairwise correlations on the properties of many-particle Fermi systems is studied. The suggested method is a generalization of the density functional method and is based on the representation of the system energy as a functional of the diagonal element of the two-particle density matrix. In this approach the exchange-correlation effects are taken into consideration without including in the model any additional assumptions concerning the properties of these effects.
Show AbstractOn radiation of gravitons with non-zero rest mass
On radiation of gravitons with non-zero rest mass
Yu.M. Loskutov
The intensity of massive graviton emission by an arbitrary spatially limited source is found and its positive definiteness shown.
Show AbstractAdvanced stage of secondary-emission microwave discharge in a relativistic Cerenkov generator
Advanced stage of secondary-emission microwave discharge in a relativistic Cerenkov generator
S.Yu. Galuzo, N.V. Odintsova
This paper presents an analysis of a steady-state mode of single-wall and double-wall secondary-emission resonance discharges in a microwave field of a Cerenkov generator with a retardation system in the form of a corrugated (diaphragmed) waveguide and in an electrostatic field of a relativistic electron beam. Relationships have been obtained for the density and thickness of the bunch formed versus parameters of the problem. The power dissipated by the secondary-emission resonance discharge in the surface metal layer is estimated.
Show AbstractSynthesis of two-component multilayer coating with a desired amplitude coefficient of reflection
Synthesis of two-component multilayer coating with a desired amplitude coefficient of reflection
A.V. Tikhonravov, V.G. Yakushkina
The problem of synthesis of multilayer optical coatings with a desired amplitude coefficient of reflection of a monochromatic wave is mathematically treated. The general algorithm for designing a multilayer surface film which is optimal with respect to the number of layers and close to optimal with respect to the total thickness, is described. The advantage of such a "quasi-optimum" coating consists in simplicity of its realization.
Show AbstractOptical non-reciprocity in collinear anisotropic diffraction on traveling ultrasonic waves
Optical non-reciprocity in collinear anisotropic diffraction on traveling ultrasonic waves
L.S. Kornienko, N.V. Nanii, 0.E. Nanii
Based on the theory of coupled waves, the amplitude and phase nonreciprocal effects have been investigated for collinear anisotropic diffraction of counter-running light waves on a traveling ultrasonic wave. The investigation results demonstrate the possibility of a substantial decrease in the sensitivity of the amplitude and phase nonreciprocal effects to the variation of the angle of incidence of the light waves on the acoustic line. The results can be used for elaborating new types of amplitude and phase nonreciprocal devices.
Show AbstractStudy of association of unlike dye molecules in aqueous solutions
Study of association of unlike dye molecules in aqueous solutions
B.D. Ryzhikov, A.M. Saletskii
Processes involved in the formation of associates of molecules of different dyes have been studied. Spectra of such associates have been identified. They consist of two bands shifted relative to the absorption bands of individual molecules toward the long-wave region of the spectrum. It is shown that the binding energy of associated molecules is close to the dispersion interaction energy.
Show AbstractVariations in the fluorescence band of a dissolved natural organic substance induced by UV laser radiation
Variations in the fluorescence band of a dissolved natural organic substance induced by UV laser radiation
S.V. Patsaeva, E.M. Filippova, V.V. Chubarov, V.I. Yuzhakov
This paper analyzes the effect of pulsed radiation of an LGl-505 nitrogen laser on the fluorescence spectra of a dissolved organic substance in water. An extensive set of sample irradiation conditions has been studied to select an optimum regime, in which the photochemical processes cause distortion of the spectrum by no more than 10%.
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