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The behaviour of a scalar optical beam at the boundary between two dissimilar nonlinear media is of fundamental interest in photonics. Here, we report the first systematic generalization of our Kerr analyses to a wider class of power-law materials. Universal refraction laws will be given, and theory-simulation agreement demonstrated.
Passive polarization converter based on the Bragg reflector with multiple defects is proposed. The structure consists of N distributed Bragg reflectors (DBR) separated by N-1 defects. Transmittance spectra for two orthogonal polarizations of the incident plane wave are presented.
We study de nonlinear optical properties of organic materials. Multiple rings appear as a CW Ar laser passes through a nonlinear organic liquid. The rings formation is due to spatial self-phase modulation and is observed with 50 mW of continuous wave of Ar laser. We show the dependence between power and rings formed. As a first approximation to value the nonlinear refractive index we use the number...
Double-charge femtosecond vortices were synthesized with the polarization-singularity beam converter [1]. The vortex was focused using moderate and high numerical aperture optics (NA = 0.45 and 0.9) to ablate fused silica and soda-lime glasses. The results demonstrate that the ablation can be controlled on a sub-micrometer scale with a high degree of repeatability.
In report modelling is produced and characteristics of new types of optical spectral-selective elements of the cylindrical form that use effect of light scattering are considered. Dispersion characteristics of indicatrisse of scattering are calculated.
We report the spatial anisotropy of the acoustooptical figure of merit M2 in LiNbO3:MgO and GaP crystals. The analysis is based on the indicative surfaces being calculated for different geometries of the acoustooptical diffraction. Basing on these results the most efficient geometries of the acoustooptical cells made of these crystals are determined. It give a possibility to increase the application...
We consider formation of ultrashort quasi-parabolic pulses in conventional silica fibers both in the near and far fields of dispersion. Through solution of nonlinear Schrödinger equation we show that in case of high soliton order N the optical wave breaking effect, occurring in optical fibers during ultrashort pulse propagation, is canceled in the far field of dispersion. This is accompanied by nonlinear...
The electromagnetic field amplification constant in the scattering of the nonrelativistic electrons by ions in the elliptically polarized light wave is theoretically studied for any intensities for which radiation amplification takes place. The anomalous amplification effect in the moderate-strong electro-magnetic field is predicted.
Polariton modes in quantum-well traps for Bose-condensation of excitons are studied. It is found that some modes can become unstable and start lasing due to exciton spectrum narrowing during condensation. A model of such lasing is developed, showing different lasing regimes and possible coherent features of recombination emission of excitons.
In the given paper we proposed an effective finite-difference scheme for a two-dimensional problem of femtosecond pulse influence on a semiconductor in the case of nonlinear dependence of light energy absorption coefficient on electric field potential.
Microscopic statistical theory of inhomogeneous broadening in InGaN/GaN quantum-well structures is developed. It is shown that inhomogeneous broadening can be described as energy-dependent daphasing time. Explicit relation between inhomogeneous broadening and spectral power density of the lateral interface potential fluctuations is derived.
We demonstrate an explicit numerical method for accurate calculation of the scattering matrix, and its poles, and apply this method to describing the multi-channel holes scattering in multiple-quantum-wells (MQW) structures. The results of calculations show that in contrast to the single quantum-well case, at some values of MQW parameters the number of S-matrix poles may exceed that of the absolute...
Theoretical model of how LBIC signal from p-n junction being scanned by two laser beams is formed was proposed. Physical effects which make impact in overall phase of the LBIC signal were pointed out. Experimental research of illuminating surface of laser diode was conducted. Experimental dependencies of the phase of LBIC signal on the coordinate of scanning laser beams were obtained. Possibilities...
In excimer lasers Chang's profile and Ernst's profile are widely used. At relation of value of interelectrode distance (h) to electrodes width (b) h/b> 0,5 significant heterogeneity of electric field on coordinate Y takes place. Research of electric field spatial dependence was carried out with help of conformal transformations application.
The map of dynamic regimes of a dual-wavelength vertical external cavity surface-emitting laser is built. The areas of continuous wave operation as well as of time-periodic, quasi-periodic and chaotic operation can be marked out in the map. A possible explanation of quite different laser behavior in those area is given.
Using numerical modeling, influence of tuning the lasing frequency within the gain band on the modulation response of quantum-well heterolasers in the GaInAs-GaInAsP system versus the modulation frequency of pump current is investigated. It is established that maximum values of the frequency width of the response band and possibilities of realization of high-speed regimes at signal transmission in...
The fine structure of the spectral distribution of the time-averaged radiation power of four electrons moving one by one along the spiral in transparent medium in relativistic case is studied. The regime of super-radiance in synchrotron-Cherenkov radiation spectrum of four electrons moving in spiral above the Cherenkov threshold is investigated.
Modeling of the random lasing in diffusive regime by Monte-Carlo method and Kubelka-Munk theory has been carried out. It has been obtained the experiment-corresponded dependencies of radiation parameters on media characteristics. The optimal samples parameters for effective lasing have been found.
The nonresonant scattering of a photon by an electron (Compton scattering) in the field of a pulsed light wave is investigated theoretically. The approximation when a pulsewidth is considerably greater than the characteristic time of the wave oscillation is considered. The analytical expressions for the amplitude and cross-section of mentioned process are derived. It is concluded, that the total cross-section...
The process of resonant scattering of a lepton by a lepton in the field of pulsed light wave in general relativistic case is studied theoretically. It is demonstrated, that the obtained resonant differential cross-section of the scattering of an electron by an electron (an electron by a positron, an electron by a muon) in the pulsed light field may be several orders of magnitude greater than the corresponding...
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