http://dspace.nbuv.gov.ua:80/handle/123456789/114629 Mon, 06 Apr 2026 03:24:23 GMT 2026-04-06T03:24:23Z http://dspace.nbuv.gov.ua:80/bitstream/id/341320/ http://dspace.nbuv.gov.ua:80/handle/123456789/114629 http://dspace.nbuv.gov.ua:80/handle/123456789/119882 Optical properties of thin metal films Kovalenko, S.A. Optical constants of metallic thin films made from: Ag, Au, Hf, Ir, Mo, Nb, Os, Pd, Pt, Re, Rh, Ru, Ta, W, Zr were determined on the basis of measured index of refraction in region of wavelength λ = 241216 Å. Two types of relations were used for the calculation. Some of them were obtained, with taking into account that refractive index of absorbing medium can be presented in the form ñ = n ± iæ. Other were obtained from Maxwell boundary condition. Both approaches give rise to very close results for æ, however the dependences n = f(λ) for λ > 200 Å are essentially different. The reasons of such differences are discussed. Fri, 01 Jan 1999 00:00:00 GMT http://dspace.nbuv.gov.ua:80/handle/123456789/119882 1999-01-01T00:00:00Z http://dspace.nbuv.gov.ua:80/handle/123456789/119881 Influence of superlattice produced by coherent light beams on the optical properties of ferromagnetic semiconductors Semchuk, O.Yu.; Gozhenko, V.V. In this work we study influence of the periodical nanostructures superlattices, produced by coherent light beams on the optical phenomena in ferromagnetic semiconductors (FMSC). It is shown that as a result of the incident electromagnetic wave diffraction on the periodical nanostructure-superlattice of electron density two waves appear in which periodic energy transfer from one wave to another takes place. We have determined the light reflection coefficient for the surface of FMSC with periodical nanostructures-superlattices. It is also shown that varying a magnitude of the external electric field one can decrease this coefficient, i.e. make FMSC «antirefractive», as well as increase it up to the case of the total reflection. Fri, 01 Jan 1999 00:00:00 GMT http://dspace.nbuv.gov.ua:80/handle/123456789/119881 1999-01-01T00:00:00Z http://dspace.nbuv.gov.ua:80/handle/123456789/119880 Size dependence of magnetic characteristics measured on separate nickel particles Nepijko, S.A.; Wiesendanger, R. Interference electron microscopy was applied to measure the coercive force, the magnetic saturation and the residual magnetization of separated nickel particles. Nickel particles with perfect sphericity and radius from 10 to 100 nm were produced directly in the interference electron microscope by means of wire explosion caused by the passage of an electric current pulse through it. We find a decrease of the magnetic saturation and an increase of the coercive force with decreasing size of the separate particles. If there are neighbouring particles, with decreasing the distance to them coercive force is characterized by more smooth size dependence and has less absolute value. This observation shows the contribution of the interparticle interaction. Fri, 01 Jan 1999 00:00:00 GMT http://dspace.nbuv.gov.ua:80/handle/123456789/119880 1999-01-01T00:00:00Z http://dspace.nbuv.gov.ua:80/handle/123456789/119879 Noise spectra and dark current investigations in n⁺-p-type Hg₁₋xCdxTe (x ≈ 0.22) photodiodes Ivasiv, Z.F.; Sizov, F.F.; Tetyorkin, V.V. The dark current and noise spectra were investigated in Hg₁₋xCdxTe (x≅0.22) photodiodes at zero and low reverse bias voltages. The photodiodes were prepared by boron implantation into LPE films. The 1/f noise is proved to be correlated with tunneling current via the deep defect states in the gap at low reverse biases U≤0.1 V. In the photodiodes, where the tunneling current is found to be dominating, the 1/f noise is observed up to frequencies 10⁴ Hz. The decrease of tunneling current results in the decrease of 1/f noise. Fri, 01 Jan 1999 00:00:00 GMT http://dspace.nbuv.gov.ua:80/handle/123456789/119879 1999-01-01T00:00:00Z