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1.
R. B. Saptsov 《JETP Letters》2007,86(10):687-691
The behavior of a weakly interacting Bose gas with a finite particle lifetime has been studied in the framework of hydrodynamic
equations under the conditions of a constant mass and energy inflow in the presence of external cooling. A spatially homogeneous
state of such a gas is shown to be unstable with respect to the formation of an inhomogeneous density structure. A possible
connection of the present results with experiments [3, 4] is discussed.
Original Russian Text ? R.B. Saptsov, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ i Teoreticheskoĭ Fiziki, 2007,
Vol. 86, No. 10, pp. 779–784. 相似文献
2.
P. A. Prudkovski 《JETP Letters》2007,86(10):652-656
The process of the domain-block structure formation at the ferroelectric phase transition in KDP-type crystals is investigated.
An effective Hamiltonian of the system is constructed; the growth of domain blocks in the vicinity of the Curie point is numerically
simulated using the Monte Carlo method, and the temperature interval of the domain block growth is determined. It is shown
that the asymptotic dependence of the mean block size on time has the form R(t) ∼ √t/lnt. In the framework of an equivalent mathematical model combining the Ising and Kosterlitz-Thouless two-dimensional models,
a kinetic equation that approximately describes the evolution of the domain-block size distribution function is derived.
Original Russian Text ? P.A. Prudkovskiĭ, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ i Teoreticheskoĭ Fiziki, 2007,
Vol. 86, No. 10, pp. 741–745. 相似文献
3.
S. N. Molotkov 《JETP Letters》2007,86(12):788-792
The simultaneous measurement of the energy and arrival time of a single-photon packet, as well as the experimental implementation
of such a measurement with the use of a parametric transformation upward in the energy (up conversion), is proposed.
Original Russian Text ? S.N. Molotkov, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ i Teoreticheskoĭ Fiziki, 2007,
Vol. 86, No. 12, pp. 901–906. 相似文献
4.
Results of an experiment on the opening of cavities in small icosahedral electrolytic-copper particles by means of an experimental
technique alternative to the chemical etching of their surface are presented. This experimental technique is theoretically
justified.
Original Russian Text ? I.S. Yasnikov, A.A. Vikarchuk, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ i Teoreticheskoĭ
Fiziki, 2007, Vol. 86, No. 9, pp. 699–701. 相似文献
5.
The thin films of a CoPd alloy in the equiatomic composition region are prepared by condensation at different substrate temperatures.
The substrate temperature is varied from the liquid nitrogen temperature to +280°C. At low substrate temperatures, the crystal
structure of the condensed films is the single-crystal blocks of the hexagonal close-packed (hcp) phase. As the substrate
temperature is further increased, the domains characterized in the initial state by the microdiffraction patterns in the form
of a diffuse halo appear in the films, and these domains have a clear-cut boundary with the regions indicated by point reflections
in the electron diffraction patterns. At substrate temperatures from +150 to 160°C, the CoPd alloy films in the equiatomic
composition region are fully amorphous. The given state is a polymorphic transformation of the martensitic type. It arises
in the martensitic transformation of the low-temperature hcp phase to the high-temperature fcc phase.
Original Russian Text ? E.M. Artem’ev, M.E. Artem’ev, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ i Teoreticheskoĭ
Fiziki, 2007, Vol. 86, No. 11, pp. 838–840. 相似文献
6.
The stimulated radiation pressure acting on an atom nonadiabatically interacting with the field of counterpropagating frequency-modulated
waves is shown to reach high values typical for the rapid adiabatic passage of the instantaneous frequency of the field of
the counterpropagating waves through resonance with an atomic transition. Under the appropriate choice of interaction parameters,
the radiation pressure changes insignificantly in a wide range of atomic velocities.
Original Russian Text ? V.I. Romanenko, L.P. Yatsenko, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ i Teoreticheskoĭ
Fiziki, 2007, Vol. 86, No. 12, pp. 868–872. 相似文献
7.
Mechanisms of the self-organization of nanosystems at the condensation of the extremely weak steady flows of copper vapors
obtained in magnetron sputtering in an ultrapure argon are studied. It is shown that the free-energy minimization near equilibrium
condensation creates prerequisites for the self-organization of statistically homogeneous layers of nanoclusters and determines
the transition to the formation of nanosystems in the form of fractal networks.
Original Russian Text ? V.I. Perekrestov, A.S. Kornyushchenko, Yu.A. Kosminskaya, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ
i Teoreticheskoĭ Fiziki, 2007, Vol. 86, No. 12, pp. 879–883. 相似文献
8.
9.
D. A. Kozlov Z. D. Kvon A. E. Plotnikov D. V. Shcheglov A. V. Latyshev 《JETP Letters》2007,86(10):662-665
The conductance of short ballistic wires with boundaries, whose curvature radius is comparable to the electron wavelength,
is investigated. It is found that, in such wires, no conductance quantization takes place. Instead, pronounced interference
effects are observed. These effects are related to the Fabry-Perot interference by the wire edges and with the mesoscopic
interference caused by the coherent scattering of electrons by the wire edges and by the impurities located in the near-wire
regions of the 2D electron gas.
Original Russian Text ? D.A. Kozlov, Z.D. Kvon, A.E. Plotnikov, D.V. Shcheglov, A.V. Latyshev, 2007, published in Pis’ma v
Zhurnal éksperimental’noĭ i Teoreticheskoĭ Fiziki, 2007, Vol. 86, No. 10, pp. 752–756. 相似文献
10.
M. M. Mogilevsky T. V. Romantsova J. Hanasz T. M. Burinskaya R. Schreiber 《JETP Letters》2007,86(11):709-711
The radiation pattern has been determined on the basis of the comparative analysis of auroral kilometric radiation (AKR) received
in the space-diversity mode by two satellites, Interball-2 and Polar. The radiation propagates in a cone with an opening angle
∼±25° and the axis aligned with the local magnetic field. The results con-firm the theoretical estimates that the source boundaries
play a significant role in the generation of the auroral kilometric radiation and in the formation of the radiation pattern.
Original Russian Text ? M.M. Mogilevsky, T.V. Romantsova, J. Hanasz, T.M. Burinskaya, R. Schreiber, 2007, published in Pis’ma
v Zhurnal éksperimental’noĭ i Teoreticheskoĭ Fiziki, 2007, Vol. 86, No. 11, pp. 819–821. 相似文献
11.
It is shown that the characteristics of the magnetorotational instability noticeably change in the presence of the inhomogeneity
of a magnetic field in which rotation occurs. A decrease in the magnetic field with an increase in the distance from the rotation
center, which is typical for astrophysical objects, can lead to a significant decrease in the threshold velocity of the object
medium rotation, as well as to mitigation of the requirements on a rotation velocity profile that are necessary for the development
of instability. Other examples that demonstrate the indicated effects are given.
Original Russian Text ? V.I. Ilgisonis, I.V. Khalzov, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ i Teoreticheskoĭ
Fiziki, 2007, Vol. 86, No. 11, pp. 815–818. 相似文献
12.
The concept of P-quasispin is used as a framework for developing a formalism for polarization transformation by means of lossless polarization-changing
optical elements for both classical and quantum multimode light fields. As an example, a classification of transformations
of this kind is presented for two-mode biphoton fields that implement the information-theoretic concepts of qutrit and ququart
(quantum systems in three-and four-dimensional Hilbert states, respectively).
Original Russian Text ? V.P. Karassiov, S.P. Kulik, 2007, published in Zhurnal éksperimental’noĭ i Teoreticheskoĭ Fiziki,
2007, Vol. 131, No. 1, pp. 37–53. 相似文献
13.
V. G. Nikiforov G. M. Safiullin A. G. Shmelev A. V. Leontev V. S. Lobkov 《JETP Letters》2007,86(10):666-669
The control of the anisotropy of the orientation of molecules in pure 1,2-dichlorobenzene, C6H4Cl2 at room temperature is demonstrated experimentally. To accomplish the optical control, the medium is exposed to non-resonant
excitation with two successive linearly polarized laser pulses with a duration of 60 fs. The state of transient anisotropy
is probed with the third pulse by detecting the ultrafast optical Kerr effect via optical heterodyne detection and synchronous
demodulation. It is shown that variations in the two parameters, the delay time between two pump pulses, and the angle between
the polarization directions of the pump pulses ensure the control of the anisotropy of the orientation of molecules in the
subpicosecond region.
Original Russian Text ? V.G. Nikiforov, G.M. Safiullin, A.G. Shmelev, A.V. Leont’ev, V.S. Lobkov, 2007, published in Pis’ma
v Zhurnal éksperimental’noĭ i Teoreticheskoĭ Fiziki, 2007, Vol. 86, No. 10, pp. 757–761. 相似文献
14.
It is shown that parametric amplification at low-frequency pumping can be implemented in coupled nonlinear optical interactions
in aperiodic nonlinear photonic crystals created by the method of the superposition of the modulation of the second-order
susceptibility. In this process, the intensities of waves with frequencies higher than the pump frequency increase monotonically
with the interaction length as in the case of the traditional process of parametric amplification at high-frequency pumping.
The dependence of the gain factor on the coupling constants of interacting waves is obtained. The process under consideration
makes it possible to ensure the tuning of the generated frequency in the ultraviolet range upon pumping in the visible range.
Analysis of the process is performed on the example of aperiodic nonlinear photonic crystals of lithium niobate.
Original Russian Text ? A.S. Chirkin, I.V. Shutov, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ i Teoreticheskoĭ
Fiziki, 2007, Vol. 86, No. 11, pp. 803–807. 相似文献
15.
The properties of a capacitive HF discharge with growing nanoparticles are studied with the use of kinetic PIC-MCC simulation.
At the initial stage of growth, the nanoparticles are shown to be localized at the interface between the near-electrode layer
and quasi-neutral plasma, where the rate of ionization by electron impact has the maximum value. At the beginning of formation
of particles, plasma parameters change rapidly and a transition between the capacitive and spatial discharge burning modes
is observed for a certain critical size of the particles. If the growth of the dust particles continues, their distribution
over the discharge becomes more uniform and the steady-state parameters of the gas-discharge plasma hardly change.
Original Russian Text ? I.V. Shveigert, F.M. Peeters, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ i Teoreticheskoĭ
Fiziki, 2007, Vol. 86, No. 9, pp. 657–661. 相似文献
16.
E. Kh. Mukhamedzhanov M. M. Borisov A. N. Morkovin A. A. Antonenko A. P. Oreshko E. N. Ovchinnikova V. E. Dmitrienko 《JETP Letters》2007,86(12):783-787
The 222 and 600 reflections near the germanium absorption K edge were studied on the Kurchatov synchrotron radiation source. The energy spectrum of the 222 reflection is caused by the
interference of the weak nonresonant and purely resonant contributions to the tensor atomic factor, whereas the 600 reflection
is purely resonant. The energy dependence of the magnitude and phase of the resonant contribution to the scattering amplitude
was determined from a change in the interference pattern. The numerical simulation of the energy spectra of reflections with
the inclusion of the dipole-quadrupole and thermally induced contributions shows that the latter is dominant at room temperature.
Original Russian Text ? E.Kh. Mukhamedzhanov, M.M. Borisov, A.N. Morkovin, A.A. Antonenko, A.P. Oreshko, E.N. Ovchinnikova,
V.E. Dmitrienko, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ i Teoreticheskoĭ Fiziki, 2007, Vol. 86, No. 12, pp.
896–900. 相似文献
17.
A new scheme is proposed for proton and light-ion acceleration to relativistic energies by superstrong laser radiation interacting
with a structured plasma target. The proposal consists in the use of two-component targets consisting of heavy and light ions,
where an ambipolar field is formed under the action of the ponderomotive force of incident radiation, and, in contrast to
the traditional schemes, acceleration starts from the front boundary of the layer. It is shown that, for the optimized target
parameters, monoenergetic GeV ion beams can be produced for radiation pulse intensities on the order of 1021−1022 W/cm2.
Original Russian Text ? A.V. Korzhimanov, A.A. Gonoskov, A.V. Kim, A.M. Sergeev, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ
i Teoreticheskoĭ Fiziki, 2007, Vol. 86, No. 9, pp. 662–669. 相似文献
18.
The differential energy spectrum of cosmic rays that is obtained on the basis of the measurements of Cherenkov radiation from
extensive air showers in an energy range of 1015–1020 eV is compared with the model of the propagation of primary particles in the interstellar medium with fractal properties.
It is found that the shape of the experimental spectrum is in good agreement with the shape of the calculated spectrum of
“all particles” at 1015–1018 eV. The average mass composition of cosmic rays that is calculated on the basis of five components does not contradict the
average mass composition obtained from the experimental data for several parameters in this energy range.
Original Russian Text ? S.P. Knurenko, A.A. Ivanov, A.V. Saburov, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ i
Teoreticheskoĭ Fiziki, 2007, Vol. 86, No. 10, pp. 709–712. 相似文献
19.
The effect of high pressure on the crystal structure of the intermetallic compounds R2Fe17 − x
Six (R = Lu or Y; x = 0 or 1.7) was studied using neutron diffraction. A correlation between changes in structural parameters and magnetic properties
under the action of high pressure, as well as under chemical substitution of Si for Fe atoms, was analyzed in terms of localized
moment and spin fluctuation models. The spin fluctuation model was found to describe more adequately the experimentally observed
increase in the Curie temperature upon chemical substitution and the decrease in this temperature under the action of high
pressure. Possible reasons for the suppression of a collinear ferromagnetic state and the occurrence of a noncollinear antiferromagnetic
state in R2Fe17−x
Six under pressure are discussed based on estimated differences between the total energy minima of these states.
Original Russian Text ? D.P. Kozlenko, V.I. Voronin, V.P. Glazkov, B.N. Savenko, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ
i Teoreticheskoĭ Fiziki, 2007, Vol. 86, No. 9, pp. 675–680. 相似文献
20.
The effect of microwave electromagnetic radiation on the resistance of the 2D electron gas in a GaAs/AlAs heterostructure
in a strong magnetic field is investigated. It is shown that, under the nonequilibrium conditions caused by microwave radiation,
the aforementioned 2D system exhibits giant oscillations of its resistance with varying magnetic field. When the measuring
current density is small, an increase in the microwave power leads to the appearance of an absolute negative resistance at
the main minimum of these oscillations, which lies near the cyclotron resonance. The experimental data are found to be in
qualitative agreement with the theory of multiphoton photoinduced impurity scattering [J. Inarrea and G. Platero, Appl. Phys.
Lett. 89, 052109 (2006)].
Original Russian Text ? A.A. Bykov, D.R. Islamov, D.V. Nomokonov, A.K. Bakarov, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ
i Teoreticheskoĭ Fiziki, 2007, Vol. 86, No. 9, pp. 695–698. 相似文献