The excitation of the terahertz (THz) high-intensity surface modes when the two-frequency p-polarized laser radiation interacts with a plasma slab is studied. It was found that the significant ...amplification of the laser field in the plasma slab occurs when p-polarized laser radiation is incident at the angle of total reflection. It is shown that, under the action of laser radiation ponderomotive forces, the resonant excitation of the THz mode of the plasma slab occurs if the frequency difference of the laser fields coincides with the eigenfrequency of the surface mode. It is established that the giant increase in the energy flux density of the THz mode occurs when p-polarized laser radiation is incident at the angle of total reflection on the near-critical plasma slab with rare electron collisions if the conditions of resonant excitation are satisfied. It is shown that in this case the energy flux density of THz mode can significantly exceed the laser intensity.
Parametric excitation of surface waves by an
s
-polarized electromagnetic wave incident obliquely on a semi-infinite supercritical plasma is considered. The growth rates and thresholds of the ...instability associated with the decay of the pump wave into two surface electromagnetic waves are calculated as functions of the incidence angle and plasma electron density. It is shown that the instability growth rate depends linearly on the electric field of the pump wave and is maximal at a plasma electron density slightly exceeding the critical density.
Propagation of electromagnetic waves in an inhomogeneous magnetically active plasma is considered. It is shown that plasma inhomogeneity gives rise to new transmission bands in which propagation of ...extraordinary localized modes becomes possible. Dispersion characteristics of such modes are determined and studied.
We construct the theory of generation of low-frequency surface eigenmodes in a rarefied plasma layer under the action of two-frequency laser radiation. We show that a significant increase in the ...energy of the plasma-layer low-frequency eigenmode occurs under resonance conditions, where the frequency of the mode coincides with the difference in laser frequencies. We establish that under the resonance conditions the energy flux density carried by the low-frequency eigenmode can be comparable to the laser-radiation intensity.
The theory of excitation of a surface electromagnetic wave (typically of a terahertz frequency range) is developed, the source of which is the thermoelectric current that arises when a charged ...inhomogeneous layer of hot electrons of submicron thickness is generated by an intense laser ultrashort pulse at the surface of a solid target under conditions of crossed electron density and temperature gradients. The efficiency of such a generation mechanism is compared with the efficiency of generation of transient surface radiation caused by a bunch of high-energy electrons leaving the target.
This study presents a modeling of spatial and size distributions of precipitates in diffusion-controlled phase transitions in metals. These data are essential for estimating the probability of ...critical cluster formation, leading to brittle fracture. The practical significance of the current research includes demonstrated ability to estimate the probability of zirconium hydrogen embrittlement based on obtained stochastic characteristics of δ-hydrides (ZrH
1.6
) morphology. The model includes a statistical analysis of serial calculations based on classical heterogeneous nucleation and growth of plate-shaped inclusions in 3
D
domain. The approach was verified with experimental data in modeling of θ’-phase (Al
2
Cu) nucleation and growth in Al–4 wt % Cu alloy. Also the paper includes an appendix with an analytical approach for evaluating the distribution function of inclusions in cluster length and mean projection length, which is the morphology metric correlating with mechanical properties. This analytical solution was also used for the verification of the numerical model.
Quasi-static surface wave propagation in a plasma layer with anisotropic electron temperature is considered. The case is analyzed where the electron temperature in the direction normal to the plasma ...boundary is considered to be zero, while in the direction along the boundary, electrons are described by the Maxwellian velocity distribution. It is shown that the modes of such a layer are described by equations for bulk plasma waves with renormalization of the electron density affecting the surface wave dispersion and damping.
Quasi-static magnetic field generation caused by the oblique incidence of a p-polarized electromagnetic wave on a semi-infinite plasma, in which the electron density exceeds the critical value, is ...considered. It is shown that the appearance of magnetic fields is caused by excitation of a nonlinear surface current at the zero harmonic of the pump wave.
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