http://dspace.nbuv.gov.ua:80/handle/123456789/114584 2026-04-05T23:54:36Z 2026-04-05T23:54:36Z Osinniy, V. Dybko, K. Jedrzejczak, A. Arciszewska, M. Dobrowolski, W. Story, T. Radchenko, M.V. Sichkovskiy, V.I. Lashkarev, G.V. Olsthoorn, S.M. Sadowski, J. http://dspace.nbuv.gov.ua:80/handle/123456789/119060 2017-06-04T00:02:32Z 2008-01-01T00:00:00Z

Thermoelectric studies of electronic properties of ferromagnetic GaMnAs layers Osinniy, V.; Dybko, K.; Jedrzejczak, A.; Arciszewska, M.; Dobrowolski, W.; Story, T.; Radchenko, M.V.; Sichkovskiy, V.I.; Lashkarev, G.V.; Olsthoorn, S.M.; Sadowski, J. Thermoelectric power, electrical conductivity, and high field Hall effect were studied over a broad temperature range in ferromagnetic Ga₁₋xMnxAs epitaxial layers (0.015 ≤ x ≤ 0.06). Thermoelectric power analysis gives information about carrier transport mechanisms in layers with both metallic and non-metallic types of conductivity and allows determination of the Fermi energy and carrier concentration. At high temperatures (T > 70 K), the thermoelectric power in GaMnAs linearly increases with increasing temperature. That indicates the presence of a degenerate hole gas with the Fermi energy EF = 220 ± 25 meV, nearly independent of Mn content (for 0.02 ≤ x ≤ 0.05). At lower temperatures, GaMnAs layers with metallic-type conductivity show an additional contribution to the thermoelectric power with the maximum close to the Curie temperature.

2008-01-01T00:00:00Z Kurbatov, D. Opanasyuk, A. Denisenko, V. Kramchenkov, A. Zaharets, M. http://dspace.nbuv.gov.ua:80/handle/123456789/119059 2017-06-04T00:03:37Z 2008-01-01T00:00:00Z

Investigations of surface morphology and chemical composition of Ag/ZnS/glassceramic thin-film structure Kurbatov, D.; Opanasyuk, A.; Denisenko, V.; Kramchenkov, A.; Zaharets, M. The surface morphology and chemical composition of Ag/ZnS/glassceramic thin-film system obtained by close-spaced vacuum sublimation technique under different grow conditions were investigated. Examination of surface profile and morphology was performed by scanning electron and optical microscopy. Chemical composition was studied by Rutherford back scattering method. Results of morphology studies enabled to determine dependence of the growth mechanism, roughness Ra, grain size D of ZnS layers on the growth conditions. The researches of chemical composition allowed to determine the concentration of compound elements and impurities, deviation from stoichiometry and thickness distribution of chemical elements.

2008-01-01T00:00:00Z Javidi, S. Faripour, H. Esmaeil Nia, M. Sepehri, K.F. Ali Akbari, N. http://dspace.nbuv.gov.ua:80/handle/123456789/119058 2017-06-04T00:03:37Z 2008-01-01T00:00:00Z

Development of a KDP crystal growth system based on TRM and characterization of the grown crystals Javidi, S.; Faripour, H.; Esmaeil Nia, M.; Sepehri, K.F.; Ali Akbari, N. A solution growth system has been built based on temperature reduction method [1]. A few KDP crystals were grown by the system up to 160×40×38 mm dimensions. Spectrophotometer transmission spectra from (100) planes of the grown crystals show about 86 % transmission in the visible region. XRD analysis, laser damage threshold, and microhardness of the crystals were determined. The etching behavior of surface features of grown KDP single crystals was studied in different etchants.

2008-01-01T00:00:00Z Hornostaev, G. http://dspace.nbuv.gov.ua:80/handle/123456789/119057 2017-06-04T00:03:22Z 2008-01-01T00:00:00Z

Optical-electronic sensor of spacecraft heat protection ablation Hornostaev, G. Block diagram and results of tests on gas-dynamic stands are represented to illustrate operation of the continuous ablation sensor, in which color light guides with a diameter of 1 mm are used. It is shown that the application of compensating light filter in the colorless channel makes it possible to create the meter invariant to external radiant fluxes applied to the heat protection covering surface.

2008-01-01T00:00:00Z