http://dspace.nbuv.gov.ua:80/handle/123456789/114582 2026-04-17T05:01:57Z http://dspace.nbuv.gov.ua:80/handle/123456789/118677 Research of the photo-voltaic effect in the two-base Ag-N⁰AlGaAs-n⁺GaAs-n⁰GaInAs-Au structure with various thicknesses of a base Yodgorova, D.M.; Karimov, A.V.; Giyasova, F.A.; Karimova, D.A. The results of research of photoelectric phenomena in the two-base Ag-N⁰AlGaAs-n⁺GaAs-n⁰GaInAs-Au structure are presented. The photo-voltaic effect observable in a wide range of the spectrum (0.4-2 µm) is explained by different signs of the photo EMF created by the separation of photocarriers in the energy barrier and from the levels of intrinsic defects as well as deep impurities of oxygen in the quasineutral base. A mechanism of photosensitivity of thin base structures with Schottky-Mott’s barrier under photovoltaic conditions is offered. 2008-01-01T00:00:00Z http://dspace.nbuv.gov.ua:80/handle/123456789/118675 Combined Fourier hologram as a noise-resist method of synthesis 2D computer-generated hologram with single diffractive order Braginets, E.V.; Girnyk, V.I.; Kostyukevich, S.A.; Kurashov, V.N.; Bushma, A.V. In this paper, a comparative analysis of two approaches to synthesis 2D hologram, which restores optical field without conjugated images, is performed. These holograms are used in embossed rainbow protective holograms to improve their forgeryproof characteristics. As a basis, one method of kinoform hologram synthesis is used, which allows to obtain the restored image of acceptable quality, but phase-matching condition is necessary to complete. That limits usage of this method in mass production of embossed holograms. The offered method of combined holograms is based on addition of optical fields restored by separated Fourier holograms. This method let us to avoid hard requirements to technical process on resist – polymer relief translating accuracy. Thus, the proposed method can be recommended for application in mass production of rainbow protective holograms. 2008-01-01T00:00:00Z http://dspace.nbuv.gov.ua:80/handle/123456789/118674 New features of surface plasmon resonance detected by modulation of electromagnetic radiation polarization Berezhinsky, L.J.; Matyash, I.E.; Rudenko, S.P.; Serdega, B.K. Using a technique based on modulation of electromagnetic radiation polarization, we studied the features of surface plasmon resonance in gold nanofilms deposited onto the surface of a totally reflecting prism (fused quartz). The angular characteristics of the polarization difference of squares of the reflectance coefficient modules for s- and p-polarized radiation, ∆ρ =|Rs|² − |Rp|² , were measured (at a wavelength λ = 0.63 µm) for metal films whose thickness varied from 0 up to 120 nm. Contrary to the results given by the traditional techniques, the characteristics of ∆ρ peak under the resonance condition. As a result, two nonresonance components were found in these characteristics. The values and shapes of their angular dependences are determined by the coefficients of internal reflection from the metal and insulator that depend on the film thickness. Application of a model with exponential dependence of the refraction and extinction coefficients on the metal film thickness led to agreement between the results of calculation from the Fresnel formulas and those obtained experimentally. It was found that characteristic parameter of the exponential corresponds to the metal film thickness value of 11±0.5 nm. 2008-01-01T00:00:00Z http://dspace.nbuv.gov.ua:80/handle/123456789/118673 Universal Electro-Optical Hybrid Logic Gates Ekkurthi Sreenivasa Rao; Satyam, M.; Lal Kishore, K. An Electro-Optical Hybrid Logic Gate is defined as a circuit which accepts either electrical or optical signals and produces both electrical and optical signals. This paper explores the feasibility to develop universal hybrid NOR and NAND gates which can be used for implementing any basic gate like AND, OR, or any complex logic function. These hybrid logic gates are proposed and implemented using phototransistors and LEDs. The logic circuits are found to be working satisfactorily for the defined logic levels. 2008-01-01T00:00:00Z