Yaremchuk I. Waveguide, plasmon-polariton and plasmon resonance effects by micro- and nanostructures for sensor’s electronics

Thesis is devoted to the study of the resonance phenomena that arise in micro- and nanostructures under conditions of optical diffraction, waveguide, plasmon-polariton and plasmon resonances. The mathematical models of the electromagnetic wave interaction with micro- and nanostructures have been developed for the research their spectral characteristics and the determination of conditions occurrence of the resonance effects. The main directions, advantages and experience of using resonant micro- and nanostructures in problems of analysis and synthesis of the optoelectronic systems have been considered. The rigorous method of coupled waves is improved by the new numerical implementation of the S-matrix algorithm to relief diffraction gratings and also due to the new representation of the functional dependence of the dielectric permittivity of the periodic structure material in the form of a modified Fourier series. The features of the waveguide and plasmon-polariton resonances in prism and grating based structures were studied. New relationships determining the connection between the parameters of the prism sensor system and its sensitivity have been established. It is shown that the highest sensitivity of the change of the minimum angle of reflection on the change in the refractive index of surrounding medium is possible in the prism structure without the waveguide layer under the surface plasmon-polariton resonance. Knowledge about waveguide resonance grating structure is developed. It is shown that reflection spectra of such structure have a single peak at normal incidence and two peaks at oblique incidence. The transmission spectrum of a multilayer structure of type dielectric layer/metal grating/dielectric layer/substrate was investigated for TE polarization. The single peak of transmission in the spectral range from 1.0 to 10.0 microns with the spectral width of 200 nm was determined. The interactions of optical radiation with the system of periodically arranged the square gold and silver nanowires on the dielectric substrate have been analyzed. The properties of metallic nanoparticles under conditions of the localized plasmon resonance have been studied. The analytical representations of dielectric permittivity of the copper, gold, silver and aluminum in a wide spectral range have been propoused. It is additionally confirmed that it is possible to shift the spectral position of the peak of surface plasmon absorption from visible wavelength range to the near-infrared spectrum by changing the thickness of the metal shell on the dielectric or semiconductor core. The features of the interaction of electromagnetic radiation with nanocomposite materials have been researched. It is shown that effective dielectric permittivity of the nanocomposite material based on a diamond-like carbon film with dispersed silver nanoparticles the best describes by the Maxwell-Garnett effective medium theory. The influence of the volume concentration of the nanoparticles, the increase of the electromagnetic interaction between them and the change of the dielectric constant of the matrix on the position of the peak of plasmon absorption have been researched. The optical properties of the diamond-like carbon film dispersed silver nanoparticles, depending on the temperature of annealing, were simulated. It is shown that after annealing of the nanocomposite the plasmon peaks are shifted to the long-wave region, broadened and become pronounced quadrupole additional absorption peaks. In order to produce prototype samples for optoelectronic systems the optimization of their structural and optical characteristics was carried out. The geometric parameters of the metallized gratings have been optimized and the sensors element has been created on its basis. Modeling and optimization of rectangular grating structures based on polycarbonate/silver and silver/silver has been carried out in order to obtain maximum gain of combining signals. It is shown that the achievement of the maximum amplification of a certain excitation wavelength is possible only for given combinations of the grating period, depth and filling factor corresponding to the resonance of localized surface plasmons on the metal interface.