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41.
Vladimir A. Andreev Margarita A. Man’ko Vladimir I. Man’ko Nguyen Cong Thanh Nguyen Hung Son Stanislav D. Zakharov 《Journal of Russian Laser Research》2009,30(6):591-598
Tomographic probability representation is introduced for fermion fields. The states of the fermions are mapped onto the probability
distribution of discrete random variables (spin projections). The operators acting on the fermion states are described by
fermionic tomographic symbols. The product of the operators acting on the fermion states is mapped onto the star-product of
the fermionic symbols. The kernel of the star-product is obtained. The antisymmetry of the fermion states is formulated as
a specific symmetry property of the tomographic joint probability distribution associated with the states. 相似文献
42.
We consider a boundary control problem for a system of second-order hyperbolic equations without the mixed derivative. The
boundary functions are constructed. We state a theorem that gives existence conditions for boundary controls. 相似文献
43.
Under study is an invariant solution of the equations of thermal diffusive convection which describes a stationary process
of a binary mixture flow in a vertical layer under the action of the pressure gradient and the buoyancy force that depends
nonlinearly on temperature and concentration. Some general properties of this solution are established and an existence theorem
is proved. Analysis of the numerical solution of the problem is carried out in the cases of a power-law and exponential dependence
of the buoyancy force on its argument. 相似文献
44.
Yu. E. Greben’kova A. E. Sokolov I. S. Edelman N. V. Andreev V. I. Chichkov Ya. M. Mukovskii 《JETP Letters》2013,98(8):460-464
Magnetic linear dichroism (MLD) is observed in polycrystalline La0.7Sr0.3MnO3 films in transmitted light. The spectral and temperature dependences of the MLD are determined for the energy E of the light wave ranging from 1.5 to 3.5 eV. The experimental spectra are fitted by a sum of Lorentzian curves. The MLD spectrum exhibits more features in comparison to the spectra of magnetic circular dichroism (MCD), which we measured earlier using the same film samples. Various temperature behaviors of the intensities of the Lorentzian components centered at different E values have been revealed. This can be related to the effect of the surface states on the magneto-optical characteristics of the samples. 相似文献
45.
The formation and evolution of a plasma in the interaction of laser radiation with gold targets are studied by computer simulations using MHD code (ESC-CASTOR). The nonlinear features of the interaction including the absorption of laser radiation, heating of the plasma components, and the deformation of the density profile under the action of the ponderomotive force are discussed. The role of these nonlinear effects together and the influence of the radiative and collisional transport in the evolution of the density profile are discussed based on the numerically obtained two-dimensional dynamical structures of the hydrodynamic parameter (electron density ne, ion density ni, electron temperature Te, ion temperature Ti), radiation temperature Tr, ponderomotive force profile, and the space-time dependencies of the absorption efficiency and the ionization rates. The radiation spectrum is analyzed and the regularities in the motion of the critical density surface are clarified. 相似文献
46.
T. M. Shneidman A. V. Andreev C. Massimi M. T. Pigni G. Vannini A. Ventura S. G. Zhou 《原子核物理评论》2015,32(2):175-179
A theoretical evaluation of the collective excitation spectra of nucleus at large deformations is possible within the framework of the dinuclear system (DNS) model, which treats the wave function of the fissioning nucleus as a superposition of a mononucleus configuration and two-cluster configurations in a dynamical way, permitting exchange of nucleons between clusters. In this work the method of calculation of the potential energy and the collective spectrum of fissioning nucleus at scission point is presented. Combining the DNS model calculations and the statistical model of fission we calculate the angular distribution of fission fragments for the neutron–induced fission of 239Pu. 相似文献
47.
N. M. Lebedeva A. A. Usikova V. V. Evstropov M. V. Lebedev V. P. Ulin V. M. Lantratov V. M. Andreev 《Technical Physics》2014,59(6):879-883
A correlation between the main parameter of a solar cell, the conversion efficiency, and its dark I–V characteristic is investigated. A formula is derived that expresses an increment (decrement) of the efficiency through a decrement (increment) of the current measured at a certain voltage (here at 2.4 V). Relationships are deduced based on which six methods for passivating the sidewalls of triple-junction InGaP/GaAs/Ge heterostructures grown by metal-organic vapor-phase epitaxy are tested to see how they influence the dark I–V characteristic. The influence of different factors, such as post-growth annealing, damaging radiation, etc., on the solar cell efficiency can be estimated by taking the dark I–V characteristic. 相似文献
48.
B. A. Andreev Z. F. Krasil’nik A. N. Yablonsky V. P. Kuznetsov T. Gregorkiewicz M. A. J. Klik 《Physics of the Solid State》2005,47(1):86-88
Excitation spectra of erbium photoluminescence in Si: Er epitaxial structures are studied within a broad pump wavelength range (λex = 780–1500 nm). All the structures studied reveal a fairly strong erbium photoluminescence signal at photon energies substantially smaller than the silicon band-gap width (λ = 1060 nm) with no exciton generation. A possible mechanism of erbium ion excitation in silicon without exciton involvement is discussed. 相似文献
49.
The electrical conductivity of V1 – xNbxO2 single crystals have been investigated over a wide temperature range covering regions of the existence of the metallic and insulating phases. It has been shown that, with an increase in the niobium concentration, the electrical conductivity of the metallic phase becomes below the Mott limit for the minimum metallic conductivity. Immediately after the metal–insulator transition, the electrical conductivity is determined by a large amount of free electrons that gradually localized with a decrease in the temperature. The temperature dependence of the electrical conductivity in the insulating phase of V1 – xNbxO2 has been explained in the framework of the hopping conductivity model that takes into account the effect of thermal vibrations of atoms on the resonance integral. 相似文献
50.
Volotka AV Glazov DA Andreev OV Shabaev VM Tupitsyn II Plunien G 《Physical review letters》2012,108(7):073001
A rigorous evaluation of the two-photon exchange corrections to the hyperfine structure in lithiumlike heavy ions is presented. As a result, the theoretical accuracy of the specific difference between the hyperfine splitting values of H- and Li-like Bi ions is significantly improved. This opens a possibility for the stringent test of the many-electron QED effects on a few percent level in the strongest electromagnetic field presently available in experiments. 相似文献