Izvestia Ufimskogo Nauchnogo Tsentra RAN最新文献

{"title":"LOW-TEMPERATURE ELECTRONIC TRANSPORT IN HYBRID THIN-FILM NANOSTRUCTURES BASED ON AN ELECTRICALLY CONDUCTIVE POLYMER","authors":"K. Arutyunov, A. Gursky, S. Monakhova, P. Panarina, E. Pozdnyakova, D. Tsoi, A. Yusupov, D. D. Karamov, A. N. Lachinov","doi":"10.31040/2222-8349-2023-0-1-42-48","DOIUrl":"https://doi.org/10.31040/2222-8349-2023-0-1-42-48","url":null,"abstract":"Most polymers are usually poor conductors of electric current and, accordingly, they can be classified as organic dielectrics. However, there is a special class of polymers, usually characterized by presence of conjugated pbonds, which provide electron delocalization, leading to electrical conductivity in the ground state of the system. In addition to such materials, there have been found polymers that are insulators in the ground state, but under the influence of external factors demonstrate a finite electrical conductivity. Polydiphenylenephthalide (PDP) belongs to the class of carbocyclic organic electroactive polymers that exhibit electrically conductive properties when an external electric field and/or mechanical stress is applied. The effect is explained by the nonzero density of electronic states inside the band gap. The depth of such states increases if the system accepts an additional electron, which indirectly provides electrical conductivity along the polymer chain. Accordingly, the presence of free electrons in contact region with a metal is an important condition for the appearance of final electrical conductivity in PDP. The working hypothesis that stimulates the proposed study is the assumption that superconducting correlations may arise in the electrically conductive state of an electroactive polymer. In the present work, the transport properties of thin-film lead-PDP-lead structures in two configurations are experimentally studied in a wide temperature range: a layered “sandwich” type and a quasi-planar “field-effect transistor” type. At temperatures below ~8 K, in layered samples, features of the PDP electron transport are observed, which can be explained by the effect of induced superconductivity in a thin film of a conducting polymer enclosed between two massive superconductors (lead). In the planar configuration, the electrical conductivity of the polymer in the plane of the structure does not appear. The reason for this observation may be related to the mechanism of the electrically conductive state of the PDP, characterized by formation of quasi-one-dimensional channels of electric current in the direction perpendicular to the plane of contact with the \"donor\" of electrons: metal in the normal or superconducting state. The effect of appearance of superconductivity in PDP requires further stidies and is potentially of significant interest for various applications in the field of practical microand nanoelectronics.","PeriodicalId":220280,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125735923","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":"THE INFLUENCE OF AN EXTERNAL MAGNETIC FIELD ON THE MAGNETIC PROPERTIES OF QUASI-ONE-DIMENSIONAL HALDANE MAGNETS (Y1-X NDX)2BANIO5 (X = 0.25 И 0.04)","authors":"E. Popova","doi":"10.31040/2222-8349-2023-0-1-75-80","DOIUrl":"https://doi.org/10.31040/2222-8349-2023-0-1-75-80","url":null,"abstract":"In the compounds of the (Y1-xNdx)2BaNiO5 family, the paradoxical coexistence of the Haldane phase and spin waves is realized. The magnetic ordering in the system is caused by the interaction of Nd3+ ions through spin fluctuations of a nickel chain, which remains internally disordered. Nd3+ magnetic moments do not deviate from the c axis of the crystal even in the presence of an external magnetic field. In this paper, for compounds (Y1-xNdx)2BaNiO5 with x = 0.25 and x = 0.04, an experimental study of the field dependence of the magnetization M(B) and the temperature dependence of the heat capacity C( T ), measured in fields B = 0; 2 and 5 T. For compounds with x = 0.25 on the dependence M(B) measured at T = 4.2 K, an anomaly was detected indicating a metamagnetic transition. Changes in the parameters of the magnetic interaction between the magnetic moments Nd along the c axis of the crystal leads to the periorientation of the magnetic moments of all Nd3+ ions along the direction of the external field B||c. For the connection with x = 0.04, no anomalies were detected on the dependence M(B), the magnetic moments of both neodymium sublattices lie along the direction of the applied magnetic field. The presence of a Schottky anomaly on the dependence C( T ) at B =0 indicates the existence of an internal magnetic field acting on the Nd3+ ion from the side of the nickel subsystem, and leading to the splitting of the main Kramers doublet of the Nd3+ ion. For a connection with x = 0.04, the Schottky anomaly shifts towards higher temperatures with an increase in the external magnetic field, and for a connection with x = 0.25, the Schottky anomaly shifts towards low temperatures only in the field B = 5 T. The displacement of the Schottky anomaly in the presence of a field is due to the ratio between the magnitude of the applied magnetic field and the component of the internal magnetic field fields с along the c axis of the crystal. For connection with x = 0.25 , the magnetic moments of the two neodymium sublattices are oppositely directed, and the Schottky anomaly of the 1st sublattice shifts towards higher temperatures, and the Schottky anomaly of the 2nd sublattice shifts towards lower temperatures. For connection with x = 0.04 с The magnetic moments of the two neodymium sublattices are directed towards the applied field, and the Schottky anomaly of both sublattices shifts towards higher temperatures, which is consistent with the experimen","PeriodicalId":220280,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129512279","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":"PROCESSES OF FORMATION OF SUPERLATTICES IN ENSEMBLES OF LC DROPLETS","authors":"O. A. Skaldin, E. R. Basyrova, Yu. I. Timirov, M. Khazimullin","doi":"10.31040/2222-8349-2023-0-1-71-74","DOIUrl":"https://doi.org/10.31040/2222-8349-2023-0-1-71-74","url":null,"abstract":"The processes of formation of lattices in cholesteric LC layers from drop domains («bubble domain») in electric fields are studied in this paper. The LC layers were subjected to tension. At a certain thickness of the LC layer, the so-called “cholesteric fingers” were formed, the system of which, with an increase in the dimensionless parameter C = d/P0 (d is the layer thickness, P0 is the equilibrium pitch of the cholesteric LC), decomposed into separate droplet domains. By varying the magnitude of the electric field, one can control both the size of these domains and the density of their packings.","PeriodicalId":220280,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131076876","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":"MAGNETOELECTRIC EFFECTS AND NEW SPINTRONICS LOGIC DEVICES","authors":"Z. Gareeva, A. M. Trochina, SH.T. Gareev","doi":"10.31040/2222-8349-2023-0-1-65-70","DOIUrl":"https://doi.org/10.31040/2222-8349-2023-0-1-65-70","url":null,"abstract":"The paper discusses new logic spintronic devices and the prospects for the use of perovskite-type multiferroics as working elements of magnetoelectric components. The principle of operation of the considered logical devices is based on the use of two components - a magnetoelectric, in which the magnetic state is recorded due to energy-efficient magnetoelectric interaction, and a spin-orbital component, in which information is read out based on the conversion of spin into charge due to the spin-orbital interaction of electrons; both components are interconnected by a nanoelectrode. When designing new logic spintronic devices, it is necessary to take into account the effectiveness of the mechanisms of ME interactions; features of spin - polarized currents and associated torques influencing magnetic moments; as well as other factors affecting the speed of switching magnetic states and the sensitivity of the device to external agents. Multiferroic materials that are promising for use as elements of ME components of new logic devices must meet a number of requirements, the most significant of which are the magnitude of the magnetoelectric coupling coefficient and the temperature at which ME effects occur. The paper considers representatives of multiferroics with a perovskite structure that meet these conditions, to some extent partially, these are high-temperature multiferroic bismuth ferrite (BiFeO3) and Ruddlesden-Popper structures, in which high-temperature ferroelectric effects are already realized and under certain conditions an ME effect is possible. The crystal structure of these compounds is considered, and the role of crystallographic distortions responsible for the manifestation of magnetoelectric properties is analyzed. Expressions are obtained for the tensor of the magnetoelectric effect as functions of magnetic order parameters, and the fundamental possibility of realizing ME effects in Ruddlesden-Popper structures containing magnetic cations is shown.","PeriodicalId":220280,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114507017","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":"STRONG GRAVITATIONAL LENSING FOR THE CASE OF NO HORIZON REGULAR CHARGED BLACK HOLES","authors":"Departement Gess, D. Ganieva","doi":"10.31040/2222-8349-2023-0-1-86-91","DOIUrl":"https://doi.org/10.31040/2222-8349-2023-0-1-86-91","url":null,"abstract":"Gravitational lensing often becomes one of the ways to experimentally test a particular theory of gravity, since it allows a visual comparison of theoretical predictions with observational data. The more massive the compact object, the stronger the visible effects are; for this reason, it seems very promising to study strong gravitational lensing by sources such as supermassive black holes. The aim of this paper is to study gravitational lensing for the case of spherically symmetric regular charged black holes with 0 < b ≤ bE and compare the obtained parameters with those calculated for spacetime without a horizon ( b > bE). Here b is an additional parameter describing the charge, and its value b = bE = 0.226 corresponds to the boundary case when the horizon disappears. In addition, using the massive objects Phe A* and M104* as an example, as well as the elliptical galaxies NGC57 and NGC163, we will compare the observed characteristics of regular charged and ordinary Schwarzschild black holes: the angular position of the asymptotic relativistic images, the angular distance between them and those calculated for the same b most images that are farthest from the center, as well as zooming in on the farthest images. The results obtained can later be compared with observational data, which will allow us to conclude that the approach used is applicable within the framework of the theory under consideration.","PeriodicalId":220280,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123727575","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":"EFFECT OF HIGH PRESSURE ON THE THERMOELECTRIC PROPERTIES OF C70 FULLERENE","authors":"D. N. Sokolovsky, Y. Volkova, V. Osadchenko, A. Babushkin","doi":"10.31040/2222-8349-2023-0-1-13-18","DOIUrl":"https://doi.org/10.31040/2222-8349-2023-0-1-13-18","url":null,"abstract":"Research has been performed into baric dependences of thermo-EMF and thermal conductivity derivative of C70 crystalline fullerene at pressures up to 46 GPa and room temperature. Pressure were created in a chamber with conducting diamond anvils. Structural transformations were recorded by changes in thermo-EMF and thermal conductivity. The pressure ranges in which there is a significant change in the thermoelectric properties of fullerene C70 are determined. The nature of the baric dependences of thermo-EMF and thermal conductivity derivative indicates irreversible structural transformations at pressures of the order of 32 GPa, due to the destruction of the structure of fullerene molecules. At pressures above 32 GPa, the thermo-EMF values become close to zero. This may be due to the formation of graphite-like carbon.","PeriodicalId":220280,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126327119","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":"EFFECT OF HIGH PRESSURES ON THE ELECTRICAL PROPERTIES OF THE OXIDE CE0.8CU3V4O12","authors":"I. Ustinova, N. Melnikova, N. Kadyrova, A. Tebenkov, A. Babushkin","doi":"10.31040/2222-8349-2023-0-1-24-27","DOIUrl":"https://doi.org/10.31040/2222-8349-2023-0-1-24-27","url":null,"abstract":"The electrical properties of the oxide Ce0.8Cu3V4O12 were studied at pressures up to 50 GPa. The samples have been synthesized by barothermal method. These compounds crystallize in the cubic symmetry with a perovskite-type structure. At ambient pressure in the temperature range from 10 to 300 K Ce0.8Cu3V4O12 - oxide has a metallic conductivity. Electrical resistance of the examined compounds measured at room temperature decreases when the pressure is raised from 16 to 50 GPa. There are two interval, where the resistance first falls rapidly with the pressure increase, and then the rate of the drop in resistance slows sharply. The baric dependencies of the magnetoresistance were obtained at the magnetic field up to 1 T. The values of the magnetoresistance are negative and amount 2% at pressure 22 GPa. The pressure range PT was determined, where a significant change of properties takes place. The results obtained for Ce0.8Cu3V4O12-oxide and the data of compounds ACu3V4O12 (A - Gd, Tb, Er, Tm) have been compared. A shift of the PT regions towards higher pressures with increasing serial number A was found. The manifestation of the effect of chemical contraction may be associated with a change in the crystal and electronic structure is assumed.","PeriodicalId":220280,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117246445","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":"ACCRETION PROCESS TO GOULART MASSLESS WORMHOLE","authors":"","doi":"10.31040/2222-8349-2023-0-1-81-85","DOIUrl":"https://doi.org/10.31040/2222-8349-2023-0-1-81-85","url":null,"abstract":"Wormholes are topological tunnels in space. At the moment, these objects remain purely theoretical, but their existence has not been experimentally disproved. The main condition for the existence of wormholes is that the matter of which the wormhole consists must be exotic, i.e. at least the тгдд energy condition ρ+p_r>0 must be violated, where ρ is the energy density, p_r is the pressure along the radial coordinate r. In classical physics, it is generally assumed that matter cannot violate the energy condition, however, experiments conducted in laboratories studying the Casimir effect have shown that negative densities ρ<0 can exist. On the cosmological scale, dark energy has a negative density. This concept was introduced to explain the reason for the accelerated expansion of the Universe. It is believed that dark energy causes an anti-gravity effect and violates the energy condition. Although the nature of dark energy is still unclear, it can be assumed that wormholes consist of this type of energy. The paper proposes to consider the accretion of dark energy and non-phantom matter (dust, stiff matter, quintessence) to a massless wormhole with a scalar field. Accretion is the process of capturing matter by a massive object (neutron star, black hole and etc.) from vicinity, which leads to a change in the mass of the central object. This process is a widespread phenomenon in the Universe and is responsible for the formation of stars and planets. There is a hypothesis that supermassive black holes in the centers of spiral and elliptical galaxies could have formed due to accretion. As a result of the analysis of the process of accretion to a wormhole, it was found that, with the accretion of dark energy ρ<0, the mass of the central object increases/","PeriodicalId":220280,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132519145","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":"POLYARYLENE ETHER KETONES AS A CONDUCTOR IN THE SOLAR CELL CURRENT COLLECTION SYSTEM","authors":"A. Chebotareva, T. Kost, A. Lachinov, S. Salazkin, V. Shaposhnikova","doi":"10.31040/2222-8349-2023-0-1-57-64","DOIUrl":"https://doi.org/10.31040/2222-8349-2023-0-1-57-64","url":null,"abstract":"The paper investigates the thermomechanical and electrical properties of a number of thermoplastic copolymers poly(arylene ether ketones) (co-PAEK) containing fluorene groups in the main chain of the macromolecule. Co-PAEKs are being studied for the purpose of their use in the contact system of a solar cell with a transparent conductive oxide (TCO) electrode and a multiwire contact grid. Polymer films are used as conductive adhesives to form an electrical contact between metal wire and TCO. The formation of an electrically conductive contact occurs during lamination at an excess pressure of 1 atm and a temperature of maximum deformation of co-PAEK, while the copolymer switches from the initial dielectric to a stable highly conductive state. Co-PAEKs with the content of fluorene groups ( q ) 5, 10, 15, 20 and 25 mol.% are synthesized, having the same molecular weight and the reduced viscosity of ~0.38 dl/g. To select the optimal contact system formation temperature for each coPAEK, the glass transition temperature ( T g) and the peak strain temperature ( T d) were determined from thermo mechanical curves. It was found that with increasing q , the temperature T g increases from 162 to 185°С, and T d from 203 to 223°С. The specific contact resistances (ρС) in the metal wire/co-PAEK/TCO (ITO - In2O3:Sn) system were determined for a round copper wire coated with indium:tin (In:Sn) solder, as well as for tin-plated wire, depending on the content of fluorene groups in the copolymer. The specific contact resistance ρС for wire with (In:Sn) solder varies in the range of 0.56-0.83 mΩ cm2, for tin-plated wire - 0.84-1.43 mΩ cm2, and co-PAEK with q = 5 mol % showed the lowest ρС in both cases. The ρC of wire/co-PAEK/ITO contacts has been studied as a function of the resistivity of ITO grown by ultrasonic spray pyrolysis on silicon substrates. The temperature dependence of the resistivity of the wire/co-PAEK/ITO contact was studied in the temperature range of 5-85°C, and a conclusion was made about the metallic type of dependence. According to the results of microscopic studies of the contact area, the typical minimum co-PAEK layer thickness between the wire and ITO after the formation of the contact was determined, which is in the range of 0.5-2.4 μm.","PeriodicalId":220280,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115260190","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":"SOME VALUE ORIENTATIONS OF UKRAINIAN PROTESTANTS IN THE URAL REGION","authors":"A. Klyashev","doi":"10.31040/2222-8349-2023-0-1-104-107","DOIUrl":"https://doi.org/10.31040/2222-8349-2023-0-1-104-107","url":null,"abstract":"This article is based on the results of field studies of members of Protestant religious organizations operating in the Southern, Middle and Polar Urals. Ukrainians represent the largest ethnic group among the Protestants of the studied regions, having a \"foreign\" origin; studies have revealed that the largest ethnic group that is the bearer of Protestantism in the Urals are Russians. The purpose of this work is to determine the value orientations of Ukrainians-members of the Protestant communities of the Ural region, the results of processing field materials are presented in comparison with data on Russian Protestants. Research evidence shows that more than half of both groups are not prosperous theologians. However, there are more potential “heroes of faith” who are ready to endure various difficulties and who do not consider achieving success in life an indispensable attribute of Christian life among Ukrainian respondents. In our opinion, this fact is explained by the fact that Protestantism historically has more rooted traditions in Ukraine than in Russia - members of the Protestant formations of the Ural regions who were born and lived for some time in Ukraine, having arrived in the Russian Federation, could bring with them more evangelically oriented values.","PeriodicalId":220280,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129923158","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}