{"title":"The Gd–Fe condensed films (structure and properties)","authors":"V. Prysyazhnyuk, O. Mykolaychuk","doi":"10.30970/jps.24.4704","DOIUrl":"https://doi.org/10.30970/jps.24.4704","url":null,"abstract":"Amorphous lms of compounds of the Gd Fe system have been obtained using the method of thermal evaporation on uoroplastic substrates. The substrate carrier temperature was 293 K. The increase in the temperature of substrates or annealing of lms carrier lead to the increase in the amount of the polycrystalline phase. The width of explored lms was 50 200 nanometers. The study of the structure of the lms was made on electron microscope UEMV-100K with use of high-temperature attachment PRON-2. Magnetic measurements were made on a vibrational magnetometer. The eld magnetization vector was parallel to a lm plane. The peak saturating eld was 300 kA/m. Structure and magnetic properties of lms and bulk samples of the Gd Fe system (GdFe2, GdFe5 and Gd2Fe17) were analyzed. Loops of magnetic hysteresis under the in uence of a small external eld were obtained. The value of the coercive force was measured. It decreases at the formation of an amorphous lm in comparison with bulk samples.","PeriodicalId":43482,"journal":{"name":"Journal of Physical Studies","volume":"2 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78407945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Nonlinear optical effects in crystals of langasite family","authors":"N. Ftomyn, Y. Shopa","doi":"10.30970/jps.24.4708","DOIUrl":"https://doi.org/10.30970/jps.24.4708","url":null,"abstract":"A calculation technique based on the Dipole Electron Shifting model is applied to investigate the nonlinear optical properties of the crystals of langasite family. The d 11 component of nonlinear optical susceptibility tensors is determined for La 3 Ga 5 SiO 14 , Ca 3 Ga 2 Ge 4 O 14 , La 3 Ga 5 . 5 Ta 0 . 5 O 14 La 3 Ga 5 . 5 Nb 0 . 5 O 14 crystals. The results of the calculations are compared with the experimental ones, described in literature.","PeriodicalId":43482,"journal":{"name":"Journal of Physical Studies","volume":"2 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78678354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Personalia, meetings, bibliography: In honour of Leonid Bulavin on the occasion of his 75th birthday","authors":"","doi":"10.30970/jps.24.3998","DOIUrl":"https://doi.org/10.30970/jps.24.3998","url":null,"abstract":"","PeriodicalId":43482,"journal":{"name":"Journal of Physical Studies","volume":"22 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83185477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"New approach in the theory of stellar equilibrium with axial rotation","authors":"M. Vavrukh, N. Tyshko, D. Dzikovskyi","doi":"10.30970/jps.24.3902","DOIUrl":"https://doi.org/10.30970/jps.24.3902","url":null,"abstract":"The study proposes a new method for the calculation of the equilibrium con(cid:28)guration of polytropes with rigid-body axial rotation. Self-consistency is based on the simultaneous use of di(cid:27)erential and integral forms of the mechanical equilibrium equation and a new variant of the perturbation theory, which is relative to the rotation in(cid:29)uence. The solutions are shown in the form of expansions for the Legendre polynomials and the functions of radial coordinate. The integral form of the equilibrium equation allows us to correctly de(cid:28)ne the set of the integration constants (the expansion coe(cid:30)cients, which depend on the angular velocity). The geometrical parameters of the stellar surface as well as the mass, volume and the moment of inertia were calculated as the functions of the angular velocity at (cid:28)xed values of the polytropic index n = 0; 1 . 0; 1 . 5; 2 . 0; 2 . 5; 3 . 0 . A comparison with the results of other authors was performed.","PeriodicalId":43482,"journal":{"name":"Journal of Physical Studies","volume":"5 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88818794","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Emitting characteristics and parameters of gas-discharge plasma on a mixture of mercury dichloride vapor with nitrogen","authors":"A. Malinina, O. Shuaibov","doi":"10.30970/JPS.24.1401","DOIUrl":"https://doi.org/10.30970/JPS.24.1401","url":null,"abstract":"The article presents the results of the studies of optical characteristics and parameters of a gas-discharge barrier-discharge plasma on a mixture of mercury dichloride vapor with nitrogen, which was the working medium of an exciplex gas-discharge emitter. The purpose of the study was to identify the regularities in the optical characteristics of a gas-discharge plasma on a mixture of mercury dichloride vapor with nitrogen; to determine the partial pressure of a bu(cid:27)er gas nitrogen at which the maximum radiation power in the blue-green spectral range in the emitters is reached; to determine the plasma parameters depending on the value of the reduced electric (cid:28)eld ( E/N is the ratio of the electric (cid:28)eld strength to the total concentration of the components of the working mixture) and also establish their values for the E/N value at which the maximum radiation power was observed in the experiment. The working mixture in the atmospheric-pressure barrier discharge was excited by a","PeriodicalId":43482,"journal":{"name":"Journal of Physical Studies","volume":"43 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90879020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
V. Karnaushenko, Y. Chornodolskyy, V. Vistovskyy, S. Syrotyuk, A. Voloshinovskii
{"title":"Energy band structure of LaF3:Sm and LaF3:Pm crystals","authors":"V. Karnaushenko, Y. Chornodolskyy, V. Vistovskyy, S. Syrotyuk, A. Voloshinovskii","doi":"10.30970/jps.24.4703","DOIUrl":"https://doi.org/10.30970/jps.24.4703","url":null,"abstract":"The papers presents the results of the theoretical calculations of the partial and total density of states of LaF 3 :Sm and LaF 3 :Pm crystals. We analyze the positions of 4 f and 5 d energy states of activator ions in the energy structure of the host material. We calculated and described electronic energy band structures of the above mentioned crystals. We made a quantitative and qualitative comparison between the energy structure of LaF 3 :Sm and LaF 3 :Pm crystals.","PeriodicalId":43482,"journal":{"name":"Journal of Physical Studies","volume":"25 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73457344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Fourier IR spectroscopy study of the radiation-thermal decomposition of water in the nano-ZrO2+nano-Al2O3+H2O system","authors":"T. Agayev, S. Melikova, N. Gadzhieva","doi":"10.30970/jps.24.2701","DOIUrl":"https://doi.org/10.30970/jps.24.2701","url":null,"abstract":"This paper presents the results of Fourier transform infrared spectroscopic studies of the radiation-thermal decomposition of water in the heterogeneous system nano-ZrO 2 +nano-Al 2 O 3 +H 2 O at various weight ratios of nano-oxides in the temperature range T = 373 ÷ 673 K and during radiation exposure. It has been established that the main intermediate products of radiation-heterogeneous decomposition of water are molecular oxygen and other oxygen-containing radical ion groups generated by gamma irradiation, as well as surface hydrides of zirconium and aluminum. Based on a comparative analysis of changes in the intensity of the absorption bands of molecular water and surface hydroxyl groups characterizing nano-ZrO 2 and nano-Al 2 O 3 as a function of temperature, the radiation-catalytic activity of nano-ZrO 2 was detected at a (cid:28)xed value of the absorbed dose. W RT (H 2 ) and its radiation-chemical yields G (H 2 ) were determined. A stimulating role in the radiation-thermal decomposition of H 2 O in a heterogeneous nano-ZrO 2 +nano-Al 2 O 3 system ( T = 373 ÷ 673 K) has been established. Fourier IR spectroscopy, nano-zirconium oxide, nano-aluminum oxide, γ -irradiation, radiation-thermal decomposition.","PeriodicalId":43482,"journal":{"name":"Journal of Physical Studies","volume":"12 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79753345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Modeling of ideality factor value in n+--p--p+-Si structure","authors":"O. Olikh, O. Zavhorodnii","doi":"10.30970/jps.24.4701","DOIUrl":"https://doi.org/10.30970/jps.24.4701","url":null,"abstract":"This paper presents the results of computer simulation of the ideality factor of silicon n−p−p structure with iron contamination. The Solar Cells Capacitance Simulator (SCAPS) was the tool used for numerical simulation of these devices. The iron concentration range of 10 − 10 cm−3, the acceptor doping level range of 10 − 10 cm−3, the temperature range of 290− 340 K, and the base thickness range of 150 − 240 μm were used in the investigation. The double diode model was used to extract the ideality factor. The following cases were considered: (i) uniformly distributed lone interstitial iron atoms; (ii) coexistence of non-uniformly distributed Fei and FeiBs. It has been shown that the ideality factor value is determined by a hole occurring on the Fei level, a trap location, and an intrinsic recombination contribution. The increase in the base thickness leads to a decrease in n value. The sign of change in the ideality factor after FeiBs dissociation depends on temperature, doping level, and iron concentration.","PeriodicalId":43482,"journal":{"name":"Journal of Physical Studies","volume":"12 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78584538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Resonant tunneling in a double-barrier Josephson junction","authors":"P. Shygorin, B. Venhryn","doi":"10.30970/jps.24.4706","DOIUrl":"https://doi.org/10.30970/jps.24.4706","url":null,"abstract":"The present paper presents an investigation of the current states in a double barrier tunnel Josephson junction. The Josephson supercurrent in tunnel multilayered structures has signi(cid:28)cant features related to the phenomenon of quantum resonant tunneling. The value of the supercurrent is very sensitive to the distance between the barriers (thickness of interior superconductor layer). This gives a possibility to fabricate the tunnel Josephson junctions with hight values of critical supercurrent. In this paper the relationship for the thickness of an interior superconductor layer has been found for which the double-barrier becomes fully transparent. We also investigated the current(cid:21)phase relation for the double barrier tunnel Josephson junction, derived the equation for the critical value of a supercurrent and calculated the skewness in the current(cid:21)phase relation for di(cid:27)erent values of the transparency of the junction.","PeriodicalId":43482,"journal":{"name":"Journal of Physical Studies","volume":"37 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72986784","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}