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Optical properties of Zn1−xMnxS and Cd1−xMnxTe films, obtained by close-spaced vacuum sublimation technique are investigated. Measuring of optical characteristics layers was carried out by spectrophotometric analysis. This research allowed to obtained spectral distributions of transmittance, reflectance and absorption coefficients of films and to expect band-gap energy of materials.
It was shown that in estimation of the electron temperature value in the gas-discharge positive column on the basis of the Schottky's relation, it is necessary to include not only pressure reduced value p0R0, but to account for the discharge system structure and the thermal regime of the whole discharge system during the discharge.
Sensor device multifunctional temperature/humidity sensitive thick-film structures based on spinel-type semiconducting and insulating ceramics of different chemical composition Cu0 1Ni 0 1Co0 6Mn1 2O4 (with p+ -type of electrical conductivity), Cu0 1Ni0 8Co0 2Mn1 9O4 (with p-type of electrical conductivity) and magnesium aluminate i-type MgAl2O4 ceramics were fabricated and investigated. These sensor...
Nowadays, the spectral optic methods for discovering and studying mineral oils in the water are widely applied to and their principle advantage towards other methods is their express-diagnostics and remote sounding. The express-diagnostics implies the rapid discovery of water pollution using optic methods in order to eliminate and liquidate pollution sources on time (tankers, terminals etc). The difference...
Results of the experimental investigations of the powerful pulsed laser radiation interaction with three-dimensional photonic structures (synthetic opal matrixes) are presented. Simultaneously with visible range luminescence X-ray generation was registered. Possible mechanisms responsible for X-ray generation are being discussed.
Transient pulse travelling inside circular microcavity has been studied theoretically using developed rigorous and efficient mathematical method. This method allows us to obtain analytical solution of the wave equation in the Laplace domain. Inverse transformation is obtained through evaluation of residues at singular points that represent excited modes of a resonator. External beam excitation is...
The structure of the optoelectronic dynamic memory. based on a method of regenerative storage and record of the optical information in a recirculating memory element with a fiber-optical delay line is offered, the multiparameter analysis of information characteristics of such system is lead.
The mathematical model and software interaction of the laser radiation with the mediums is proposed. Software has been developed on basis of Monte-Carlo method. The heterogeneous properties of the medium, features of the absorption and scattering in individual layers are taken in account in calculations. Simulation distribution of the temperature in skin layers having vascular pathology under the...
Non-singular coordinate transformation is investigated and expressions for a component of permittivity and permeability are received. Numerical modelling of the corresponding device of invisibility is lead. It is shown that the total size of scattering from the invisibility device in a for zone corresponds to size of scattering from the perfect electric conductor cylinder which is “base” of coordinate...
In the paper, we investigate in details switching ON and switching OFF dynamics of the wideband optical filter on the basis of nonlinear photonic crystal which possess all-optical bistability properties. The all-optical flip-flop using ultra-short pulses with duration lower than 200 fs have been demonstrated in such filters.
The heat processes are considered for continuous wave GGG:Nd, YAP:Nd, YVO4:Nd and YAG:Nd microlasers. The distribution of the temperature as well as the thermo-induced changes of the refraction index and the deformations is determined. At the given distributions of the refractive index and the deformations the components of (ABCD) - matrix, the laser beam waist and the divergence are determined in...
A novel definition of optical contrastivity for complicated structures as relative total gap taken over a chosen range of frequencies is introduced. The notion introduced for ordered 1D systems retains its meaning for 2D, 3D and disordered structures. The contrast sensibility to parameters is analyzed for a wide area.
Here we discuss optical properties of the holographic sensors - a new class of analytical optical devices. We discuss the issue of sensors operating mode choice of and the influence of their light-scattering properties. Ways to study the spatial uniformity of the holographic sensors are discussed.
application of tilted holographic photopolymer Bragg gratings in the capacity of reflective gratings is considered theoretically. The negative appearances caused by a volume shrink-age of medium and changes of an average refractive index were taken into account. It is offered two different ways of recording/reading similar reflective gratings over the range 300–1000 nm that matches to the transparence...
Spectra of magnetooptical polaritons in nonlinear magnetogyrotropic medium at presence of magnetostatic field are received. Nonlinear internal ion polarization arisen under the influence of high-frequency electromagnetic field is taken into account. The polariton spectra subjected to strength and direction of the external magnetostatic field are calculated.
We show that any solution of the paraxial parabolic equation can be simply transformed to some nonharmonic in time exact solution of the wave equation. On the basis of this observation, we generalize the known Bateman-type waves and present a family of exact solutions of the wave equation involving an arbitrary function, waveform. Argument of this function is much similar to that which appear in general...
A magnetized ferrite waveguide situated between two half free spaces is investigated theoretically. Maxwell's equations and Snell's law are used to calculate the reflected and transmitted powers of the structure numerically. It is demonstrated that, maximum reflectance and minimum transmittance can be obtained by tuning the applied magnetic field.
Interconduction band gain without global inversion is obtained by engineering conduction band dispersion relations with dilute N resonant centres. We recover the expected dispersive gain shape for similar masses and contrasting results if the effective masses characterizing the relevant subbands are very different.
In this work, we investigate the influence of the substrate material on the temperature distribution in the active region of the nitride-based quantum well UV light-emitting diodes. Results of mathematical modeling show that the application of the GaN substrate leads to a reduction of the averaged temperature in the active region of a few tens of degrees Kelvin comparing with the sapphire substrate.
We have realized computing and analysis current-voltage characteristic. For this purpose we use transfer matrix method combined with Liouville-fon-Neymann equation. Obtained system of ordinary differentional equations describes time dependent changes of transition probabilities and concentrations in single-molecular junction. System was solved using Runge-Kutta method and time dependent polarization...
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