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SURFACE ELECTROMAGNETIC WAVES OF OPTICAL RANGE (PLASMONS-POLARITONS): PROPERTIES AND APPLICATION

 

Surface plasmon polaritons (SPPs) are electromagnetic excitations, in wich electromagnetic field in dielectric is coupled to collective electron oscillation in metal, and propagate along and is tightly bound to metal/dielectric interfaces. First, we present an overview of SPPs in the optical range and their applications in optoelectronics and sensorics. We further present the main research results achived by the author in this area.

The Manifestation’s Research of the Pair Association in the Pyridine’s Ir-Spectrums by the Matrix Isolation Technique

The calculation of structure, frequencies of normal fluctuations and the strips intensity in IR-spectrums of five dimer of pyridine with hydrogen communication  has been performed by the matrix solation technique B3LYP/6-311+G (d, p). The number’s modeling of the difficult oscillatory contours in the pyridine’s IR-spectrum was executed taking into account the intermolecular interaction.

THE INFLUENCE OF MORPHOLOGY, CONDITIONS OF PRODUCTION AND EXTERNAL EFFECTS ON NANOPARTICLES’ (IN TERMS OF IRON) DIELECTRIC PROPERTIES

It was shown that the complex research of iron nanoparticles properties by different methods, supplemented each other, permit to receive the data about the interior sizes of nanoparticles, a number of physical properties of particles, their dependence on frequency and changes produced by various influences. It was found that the conductivity of nanoparticles changed under the square dependence σ = σo*ω2.

THE ABSORPTION SPECTRA AND THE RESONANT FREQUENCY OF THE STRUCTURE OF THE "MAGNETIC NANOCOMPOSITE COATING – MICROSTRIP LINE"

This paper aims to look into microwave absorption spectra of «mag-netic nanocomposite coating – microstrip line» structure, containing magnetite Fe3O4 nanoparticles. The resulted spectra allowed to define the specific resonance frequencies of the structure under investiga-tion and to figure out the material parameters of the nanocomposite coating, that are, an effective magnetization, a volume fraction of magnetic nanoparticles in the coating as well as a magnetic crystal-line anisotropy filed.

Fluorescent Properties of Quantum Dots During Silanization Process

Quantum dots (QDs) are fluorescent semiconductor nanoparticles with unique optical properties. For bioapplication QDs have to be water-soluble. Here we describe one of common hydrophilization approaches – ligand exchange on silica precursors molecules and investigate fluorescent properties during this process.

Тhе Quasipotential Approach to the Syperfine Splitting of Muonic Hydrogen and Positronium

For the description of the two-partial atoms spectrum in quasipotential approach the relativistic amplitude is used. The interrelation of scattering amplitude expressions, corresponding to quantovoelektrodinamic corrections in various orders is traced. Arising from the accounting of delay effect the additional logarithmic corrections of the sixth order to the constant of fine structure in the bound level superfine shift are analyzed.

Creating and Fluorescence of the Multilayer Langmuir – Blodgett Films of CdSe/CdS/ZnS Quantum Dots

Multilayered structures composed by Langmuir – Blodgett films of CdSe/CdS/ZnS quantum dots functionalized by oleic acid and fluorescent at 525 and 631 nm were prepared and studied by fluorescent spectroscopy. It was shown that fluorescent spectra of the nanosized multilayered film consisting of different QD layers have complex character and can be rearranged with relative positions of QD layer and laser beam that open possibility to operate the fluorescent intensity of every QD layer

Range of Gamma Quanta in the Beryllium Target

Changes of an initial brake range of gamma quanta in a sample are analysed. It is shown that the main mechanism influencing g quanta range form in a sample of beryllium is Compton’s effect. In work this amendment is considered in the analysis of an exit of photoneutrons. However unlike the models considered in other works at the accounting of Compton dispersion parametrization isn’t used.

Power Range of Photoneutrons from 209Bi at Е γmax = 12 MeV

On a bunch of brake radiation of the betatron the power range of photoneutrons from 209Bi is measured. Measurements are executed by means of a scintillation spectrometer on the basis of a stilbene crystal with discrimination γ-radiations in an impulse form. The obtained data are compared with known of literature and analyzed on the basis of evaporation model.

Research of the Contact Pads Topology Influence on the Parameters Reproducibility of the Current Oscillations in Mesa-Planar Structures Based on Semi-Insulatinggallium Arsenide

Experimental results of research the influence of the electric field distribution between the pads of mesa-planar resistor structures based on semi-insulating n-GaAs are represented. These influence by changing pads topology (plane-parallel, flat-pointed, counterpointed and concave-pointed) was studied for the current oscillations parameters (the threshold voltage, frequency and amplitude of current oscillations) reproducibility increasing.

Microwave Photonic Crystals. New Application Areas

The theoretical and experimental justifications of the possibility to use the microwave photonic crystals for the creation of broadband loads have been presented. The possibility to simultaneously determine the thickness and the conductivity of nanometer semiconductor layered structures by use of the microwave photonic crystals has been shown. The possibility of electrical control of the microwave photonic crystals amplitude-frequency characteristic has been experimentally demonstrated.

Digital Speckle Photography with Correlation Processing of Spatial Spectrum of Specklegram for Determination of Micro Displacement of Scattering Object

The method of digital speckle photography for determining of speckle pattern displacement with sub-pixel accuracy using correlation processing of summary spatial spectrum of speckle patterns is considered in this article. It is assumed that displacement of speckle pattern is caused by deformation or displacement of an object with a scattering surface. The method of phase shift of interference pattern in diffraction halo is proposed for expanding the lower limit of measuring range of speckle pattern displacement to subpixel values.

Self-mixing Interferometry of Distance at Wavelength Modulation of Semiconductor Laser

Theoretical description for method of distance measurement at alteration emission wavelength of semiconductor laser, operated in self-mixing regime, has been presented. The result of computer modeling of self-mixing signal at harmonic wavelength modulation of laser diode has been represented. Spectral harmonic selection of low-frequency spectrum of self-mixing signal for distance measurement has been theoretically substantiated.

Optical Clearing of Human Eye Sclera by Aqueous 30%-Glucose Solution

In this work, optical clearing of human eye sclera in vitro under action of aqueous 30% glucose solution was studied. It was shown that diffusion of glucose in tissue results in significant decrease of light scattering, which manifests itself in both decreasing reflectance and increasing transmittance of the samples. At that, absorption coefficient does not change. Measurements were performed with spectrophotometer CARY-2415 in the spectral range from 400 to 800 nm by a standard method.

The Liquid Crystal Modulator on the Basis of the Waveguide Mode in the Twist Structure with the High Twist Angle

On the basis of the analysis of color characteristics of different LC display units the criterion for an assessment of an unchromaticity of black-and-white images is entered. For the adequate description of the optical properties of the LC modulator the necessary set of three characteristics is offered: contrast of the modulator, average on a range; the average on a range passage of the modulator for a status «is opened»; a modulator akhromatichnost is «open» for a status.

Model of the Miniature Modulator for Microwave Devices

In the given paper the model of the miniature modulator for microwave devices is observed. The modulator consists of the master oscillator, which provides four series of the impulses, and of the inverter commutated with the surge generator providing a plate supply of the load. The pulsing plate supply of the load is stabilized by the current regulator on the unipolar transistor. The control and check unit realize the general control of the modulator. The optimal characteristic of the work of a magnetron is provided by the 16-digit microcontroller.

Comparison of Methods for Phase Synchronization Diagnostics from Test Data Modeling Nonstationary Signals of Biological Nature

Three methods of phase synchronization diagnostics from time series are compared by the analysis of test data. These data reproduce the statistics of experimental temporal realizations recorded from the system of human cardiovascular system autonomic control.

Time-delayed Feedback Control of Coherence Resonance. Experimental Study

In the paper a possibility to control the behavior of dynamic systems under conditions of coherent resonance using delayed feedback is proved experimentally. This problem is studied on the classical example of excitable system, which is the FitzHugh – Nagumo oscillator, as well as on the example of the Van der Pol oscillator with hard excitation, which also demonstrates the regime of coherent resonance. In both cases, when changing the delay time the feedback loop can both enhance and suppress the effect of coherent resonance.

Total Conversion of Terahertz Wave Polarization by Graphene Microribbon Array without Magnetic Field

The polarization conversion of terahertz radiation by the periodic array of graphene microribbons located at the surface of a high-refractiveindex dielectric substrate (prizm) is studied theoretically. Polarization conversion at the plasmon resonance frequencies takes place without applying external DC magnetic field. It is shown that giant (up to total) polarization conversion can be reached at the total internal reflection of THz wave from the periodic array of graphene nanoribbons.

On the Use of Optical Clearing in Strengthening the Sclera by Collagen Photocrosslinking

In the paper, the first evaluation results on the effect of optical clearing on the efficiency of the technique of eye sclera strengthening through the formation of riboflavin / ultraviolet collagen photocrosslinks are presented.

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