Faculty of Physics
M.V.Lomonosov Moscow State University
Condensed matter physics

Nanotechnology and molecular physics

N.N. Sysoev, A.I. Osipov, A.V. Uvarov

Moscow University Physics Bulletin 2009. 64. N 1. P. 1

The paper contains a brief review of the modern status of nanotechnology. We present a general description of nanotechnology research, viz., the financing, growth of the number of publications, and the contribution of Russian scientists. The methods of nanomaterial manufacturing and diagnostics, properties of nanomaterials, and their applications are considered separately. The main attention is devoted to carbon nanomaterials: carbon nanotubes and fullerenes. We stress the close connection between nanotechnology and molecular physics.

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Theoretical and mathematical physics

Mechanical and electrical streams in planets and stars

V.I. Grigoryev, V.S. Rostovsky

Moscow University Physics Bulletin 2009. 64. N 1. P. 10

Empirical data about the latitudinal asymmetry of the geomagnetic field are used to obtain quantitative estimates of the westward geographic drift.

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Weakly bound electrons in an external magnetic field

I.V. Mamsurov$^{1}$, F.Kh. Chibirova$^{2}$

Moscow University Physics Bulletin 2009. 64. N 1. P. 13

The electron behavior in a spherical symmetric potential well in the presence of an external magnetic field is studied. The transcendental equation for the energy spectrum is derived. The energy of the bound state is approximately calculated. The electron wave function and the probability current are found.

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Dependence of the efficiency of a posteriori estimation of the solution accuracy of an elliptic boundary-value problem on the problem data and estimation algorithm parameters

A.N. Bogolyubov, M.D. Malykh, A.A. Panin

Moscow University Physics Bulletin 2009. 64. N 1. P. 17

Based on numerical experiments, we analyzed the relationship between the efficiency of the error estimation method proposed by S.I. Repin for approximate solutions of elliptical equations and the problem data and estimation algorithm parameters used.

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The fermi-particles model spectrum

D.S. Golikov

Moscow University Physics Bulletin 2009. 64. N 1. P. 22

We consider the system of Hamilton’s equations and the system of variation equations whose solutions determine the excitation spectrum of the model fermion system.

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Controllable dissipative tunneling in an external electric field

V.Ch. Zhukovskii$^{1}$, O.N. Gorshkov$^{2}$, V.D. Krevchik$^{3}$, M.B. Semenov$^{3}$, E.V. Groznaya$^{3}$, D.O. Filatov$^{2}$, D.A. Antonov$^{2}$

Moscow University Physics Bulletin 2009. 64. N 1. P. 27

We have studied the problem of controllable dissipative tunneling in the system of tunnel-binding quantum dots (quantum molecules) and in the “AFM/STM cantilever tip-quantum dot” system, which was simulated by a double-well oscillator potential interacting with a heat-bath in an external electric field. We show that theoretical results qualitatively describe some experimental I–V curves for “the AFM/STM cantilever tip-zirconium quantum dot” system. These experimental curves were obtained in the Research Institute of Physics and Technologies at the State University of Nizhniy Novgorod.

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Investigation the spectral scattering characteristics of a nanohole in a film

I.V. Grishina$^{1}$, Yu.A. Eremin$^{2}$, A.G. Sveshnikov$^{1}$

Moscow University Physics Bulletin 2009. 64. N 1. P. 33

Based on the method of discrete sources, an analysis is made of the spectral scattering characteristics of a nanohole in a metal film applied onto a glass prism. An effect of extremal electromagnetic energy leakage through the hole is discovered in the evanescent wave formation region.

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The correspondence between Casimir pressure and energy in one-dimensional field models

Yu.S. Voronina, P.K. Silaev

Moscow University Physics Bulletin 2009. 64. N 1. P. 38

We propose a method of calculation of Casimir pressure using the Green function for one-dimensional case. This method yields the renormalized pressure if an external field is absent, otherwise it permits us to calculate the dependence of pressure at one boundary on the other boundary’s coordinate. The calculated pressure permits one to obtain the Casimir energy for the systems under consideration.

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Operators of observables for a neutral particle with anomalous magnetic moment in an electromagnetic field

E.V. Arbuzova$^{1}$, A.E. Lobanov$^{2}$, O.S. Pavlova$^{2}$

Moscow University Physics Bulletin 2009. 64. N 1. P. 44

The explicit form of operators of kinetic momenta and spin projection for a neutral particle with an anomalous magnetic moment in constant homogeneous electromagnetic field is found. The possible applications of the obtained results in neutrino physics are considered.

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The threshold of subharmonic parametric excitation in the bragg gap of a periodic structure

I.G. Zakharova, M.V. Komissarova, V.F. Marchenko

Moscow University Physics Bulletin 2009. 64. N 1. P. 48

Methods of excitation of the subharmonic whose frequency lies within the forbidden band gap of a periodic structure are discussed. The dependences of threshold values of in-phase pumping on structure parameters are found.

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Optics and spectroscopy. Laser physics

Quantum nonlinear resonance in a strong electromagnetic field

P.V. Elyutin

Moscow University Physics Bulletin 2009. 64. N 1. P. 50

The motion of a one-dimensional quantum weakly anharmonic system under the influence of harmonic external field is treated in the range where the transition frequency between the neighboring levels is close to the frequency of the harmonic field (quantum nonlinear resonance). The case of the strong external field, in which the Rabi frequency for the transitions is large in comparison with the field frequency, is studied. The expression for compact wavepackets of quasienergy states that change their content and width periodically (and, possibly, strongly), is obtained.

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Formation of elliptically polarized ring-shaped electric field structures on the self-focusing of light in an isotropic medium featuring a spatially disperse nonlinearity

A.A. Golubkov$^1$, V.A. Makarov$^1$, I.A. Perezhogin$^2$

Moscow University Physics Bulletin 2009. 64. N 1. P. 54

The possibility is demonstrated that the self-focusing of an elliptically polarized beam in a medium featuring a spatially disperse cubic nonlinearity can give rise to several radially symmetric ring-shaped regions of the same sense of rotation (right or left) of the electric-field vector in the cross-section of the beam. The formation dynamics and propagation features of such electric field structures are studied for various parameters of the incident radiation and nonlinear medium.

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Condensed matter physics

Specificities of light-induced relaxation of metastable defects in amorphous hydrogenated silicon

I.A. Kurova, N.N. Ormont

Moscow University Physics Bulletin 2009. 64. N 1. P. 58

The thermal relaxation kinetics of light-induced metastable defects in a-Si:H was studied prior to and after partial relaxation in the dark and in a dim light. The film lighting was found to change the relaxation rate of the defects and their distribution in relaxation time. This was demonstrated to be due to the concurrent light-induced relaxation and formation of the defects.

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The effect of a nonmagnetic Zr layer on the magnetic and magneto-optical properties of Fe/Zr and Fe/Zr/Fe thin-film systems

E.E. Shalygina$^{1}$, G.V. Maksimova$^{1}$, A.N. Shalygin$^{1}$, L.V. Kozlovskii$^{2}$

Moscow University Physics Bulletin 2009. 64. N 1. P. 62

The magnetic and magneto-optical properties of nanocrystalline Fe/Zr and Fe/Zr/Fe thin-film systems have been studied using the magneto-optical method. The strong effect of Zr layer thickness t$_{Zr}$ on the magnetic properties of Fe/Zr samples was discovered. It was found that the value of the saturation field of the Fe/Zr/Fe systems oscillates as a function of t$_{Zr}$, which is explained by the oscillating character of the exchange interaction between ferromagnetic layers via a Zr spacer with the change in t$_{Zr}$. It was established that the values of the transverse Kerr effect depend on the thicknesses of both magnetic and nonmagnetic layers.

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The influence of an electric field on ferroelectric-antiferroelectric frustration in smectics

A.V. Emelyanenko

Moscow University Physics Bulletin 2009. 64. N 1. P. 67

A microscopic theory describing smectic phases frustrated between ferroelectric and antiferroelectric states is generalized to the case where an external electric field is present. It is shown that two threshold values of the electric field. The first one corresponds to helix unwinding, while the second corresponds to destruction of the phase with frustrated elementary cells. The obtained theoretical conclusions are compared with the experimental results.

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Biophysics and medical physics

The influence of the electromagnetic radiation of low intensity on toxicity of an aqueous medium

M.G. Gapochka

Moscow University Physics Bulletin 2009. 64. N 1. P. 70

The toxicity of solutions of phenol in combination with cadmium and cobalt for a culture of micro-seaweed and the opportunity of decreasing their toxicity by the influence of electromagnetic radiation in the range of the highest frequencies (UHF irradiation) are studied. The synergism between phenol and metals and a decrease in their toxicity under the influence of electromagnetic radiation are revealed.

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Astronomy, astrophysics, and cosmology

Recognition of gravitation impulses on a correlated non-Gaussian noise background

A.V. Gusev, V.N. Rudenko

Moscow University Physics Bulletin 2009. 64. N 1. P. 73

We consider the problem of gravitation-wave impulse recognition against the background of correlated noise produced by resonance gravitational antennas. A new algorithm for the joint processing of data recorded by spatially separated gravitational detectors is obtained. The algorithm is an alternative to the coincidence scheme, which is traditionally used in gravitation-wave experiments. It is based on the principles, well known in statistical radiophysics, of $joint$ detection and parameter estimation in quasi-deterministic signals

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Physics of Earth, atmosphere, and hydrosphere

Migration of earthquake hypocenters from great depths to the Earth’s surface

E.V. Voronina, A.V. Lyusina

Moscow University Physics Bulletin 2009. 64. N 1. P. 77

This paper discusses studies of the migration over time of hypocenters from great depths to the Earth’s surface. The calculations are based on the notion that surface fracturing of the external lithosphere corresponds to brittle fracturing, while internal lithosphere fracturing, accompanied by a decrease of earthquake hypocenter depth, corresponds to ductile fracturing. A procedure for calculating periods of the rising of earthquake sources in an elastic-plastic environment is suggested. Finally, it was revealed that the rising of hypocenters to the surface takes approximately 8–10 years.

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The ionosphere over Alaska during a storm period in October 2003: Radio tomography and data obtained with GAIM/IFM ionospheric models

E.S. Andreeva$^{1}$, V.E. Kunitsyn$^{1}$, E.A. Leonyeva$^{1}$, Yu.N. Fedyunin$^{1,2}$

Moscow University Physics Bulletin 2009. 64. N 1. P. 84

The results of comparative analysis of data obtained using GAIM and IFM ionospheric models with radio tomographic cross-sections of the ionosphere and ionosonde measurements in Alaska during a geomagnetic storm at the end of October 2003 are reported. The results of comparisons (64 cross-sections) showed the GAIM model data to be significantly closer to radio tomographic reconstructions than those of the IFM model. However, GAIM divergence from radio tomography data drastically increases with the enhancement of ionospheric disturbances.

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Theoretical and mathematical physics

Resonance enhancement of electron-phonon interaction

Moscow University Physics Bulletin 2009. 64. N 1. P. 89

A superconducting state near the phase transition curve from paramagnetic phase to superconducting phase for perovskites La$_{2-x}$Sr$_{x}$CuO$_{4}$ and YBa$_{2}$Cu$_{3}$O$_{6}$ is considered. Expressions for effective parameters of electron-spin-phonon interaction are obtained. It is shown that the critical temperature of the phase transition from paramagnetic phase to superconducting phase Т$_{c}$ is determined by the enhancement of electron-phonon interaction by spin fluctuations of exchange type.

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Physics of nuclei and elementary particles

Model-independent Breit-Wigner parameters of S$_{11}$(1535) and S$_{11}$(1650) nucleon resonances from experimental data on η meson photoproduction on protons

E.V. Balandina, E.M. Leikin, N.P. Yudin

Moscow University Physics Bulletin 2009. 64. N 1. P. 91

The results of phenomenological partial-wave analysis of angular distributions for the process $\gamma\rho\rightarrow\eta\rho$ measured at the Tohoku University (Japan) and model-independent estimates of Breit-Wigner parameters of S$_{11}$(1535) and S$_{11}$(1650) nucleon resonances obtained based on these data are presented.

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Propagation and interaction of ultra-short pulses in quadratic crystals with controlled dispersion

V.E. Lobanov, A.P. Sukhorukov, V.A. Chernykh

Moscow University Physics Bulletin 2009. 64. N 1. P. 95

Propagation of ultra-short optical pulses in an environment with quadratic nonlinearity and modulated dispersion is studied. It is shown that periodic modulation of the velocity-mismatch sign and of the third-order dispersion coefficient allows one to suppress pulse scattering and decompression, which noticeably increases their interaction efficiency.

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Condensed matter physics

Features of the $E_{2g}$ phonon mode in $MgB_{2}$

V.V. Rzhevskii

Moscow University Physics Bulletin 2009. 64. N 1. P. 98

A model estimate of the energy eigenvalues of the $E_{2g}$ phonon mode of the ion vibrations in the plane of boron atoms is obtained. It is shown that the anharmonic contribution to the energy of $E_{2g}$ monotonously increases with the increase in $z=A_4/A_2^2$, where $A_4$ is the fourth-order anharmonic coefficient and $A_2$ is the harmonic constant. The results agree with the estimate in the Hartree-Fock approach. However, the discrepancy between these results and Raman spectroscopy data indicates the necessity to account for the influence of the electron-phonon interaction on the energy of $E_{2g}$ in more detail.

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Chemical physics, physical kinetics, and plasma physics

Stages of an electric discharge gliding on a water surface

A.F. Aleksandrov, D.N. Vaulin, A.P. Ershov, V.A. Chernikov

Moscow University Physics Bulletin 2009. 64. N 1. P. 100

Three stages of a pulse electric discharge were revealed. The discharge occurred in the atmosphere along a free water surface between a tip placed at some distance from the water surface and a distant electrode immersed in the water.

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