No abstract available

[en] In this paper is presented a method to find the conditions of existence for anisotropic different plasmas which present the same reflection coefficient. The analytical dependence of the complex reflection coefficient on the plasma parameters wao examinated. Then the numerical calculations were made with the use of a computer. The results of these calculations have been plotted on a special diagram thus allowing the direct determination of the plasma parameters ωsub(p)/ω, ωsub(b)/ω, ν/ω with the reflection coefficient being known from measurements and on of the above mentioned parameters, or to establish what are the distinct sets of values for the plasma parameters ωsub(p), ωsub(b), ν for which the same reflection coefficient is obtained. The method also could be applied in two both cases of plasma explored by means of TEM mode and by guided waves respectively. (authors)

[en] Charged particles energy losses in high-temperature plasma with a magnetic field are calculated, dielectric plasma permittivity found with quantum correlation functions being used. For strong magnetic fields when the lambda << Re << asub(e) condition is realized (lambda is de Broglie electron wave length, Re - Larmour radius, asub(e) - Debye shielding radius), the value of the Coulomb logarithm being a magnetic field function in this case is calculated and energy losses anisotropy for different direction of test particle with velocity (5) in relation to the magnetic field is analyzed. The calculation is performed for slow particles with V << νsub(e) , where νsub(e) is thermal electron velocity. It is shown that the energy losses velocity of the slow test particle in case of motion across the strong magnetic field can approximately 1.2-1.5 times surpass the losses in case of motion along the magnetic field

No abstract available

[en] We show that a turnover from the classical Debye to the two-power-law relaxation behavior, observed in the majority of physical systems, is associated with a new type of a coupled memory continuous-time random walk driving a fractional dynamics. We derive a general class of the two-power law relaxation responses which is able to reproduce all of the observed relaxation patterns, given by the low- and high-frequency power-law exponents falling in the range (0,1]. (authors)

[en] We consider the influence of the phase of internal coupling within a nonlinear Kerr-like coupler on entanglement decay. Assuming that the coupler interacts with an external reservoir, we show that by changing this phase we can obtain qualitatively various types of entanglement decay. In consequence, we are able to control the occurrence of sudden death and sudden birth phenomena.

[en] Based on complementary fractal geometry structures, we design a novel infrared quasi-three-dimensional (3D) nanocavity with a localized enhanced field with multiband resonant frequencies. The fractals offer the nanostructure two important characteristics, multiband functionality and a subwavelength effect. The electric field, power flow, and the field intensity distributions are given to indicate the internal mechanism of the localized enhanced field in the nanocavity. Additionally, the effective medium method is established to retrieve the permittivity and impedance of the structure. It is shown that a strongly enhanced localized field is achieved in the nanocavity at two different resonant frequencies by using the finite difference time domain method. The field intensity in the nanocavity is enhanced by a factor of up to 60 times over that of the incident light because of the important contribution of the loss factor in the permittivity. The surface plasmon hybridization is thought to play an important role in the strong localized field enhancement. The multiband property and high localized intensity offer the nanocavity great potential for applications in surface enhanced Raman scattering and other nanoscale novel devices. (paper)

[en] Bi₁.6Pb₀.4Sr₂Co₁.8O_x thermoelectric ceramics with small Ag additions (0, 1, and 3 wt.%) have been successfully produced by a sol-gel method via nitrates. Microstructure has shown a reduction on the amount of secondary phases and an increase on the bulk density with increasing Ag contents. The microstructural evolution, as a function of Ag content, is confirmed with the electrical resistivity values which show an important decrease for the 3 wt.% Ag samples, leading to maximum power factor values of about 0.025 mW/K2.m at room temperature, which is about two times higher than the obtained for the Ag-free sintered samples. (Author) 40 refs.

No abstract available

[en] In ion conducting solids, we show that the frequency-independent dc conductivity and the frequency-dependent polarization conductivity are two distinct physical processes and the same time they are related to each other. The dc conductivity is a barrier hopping short-time relaxation mechanism, whereas, the polarization conductivity is a modified barrier hopping with a long-time relaxation mechanism in the polarization process. Both these processes are shown to be related through an exponent in the relaxation process and it signifies trapping of hopping charge carriers due to the disorder in the solids. The polarization conductivity data are analyzed and results are reported. (author)