Библиотека института физики им. Л.В. Киренского СО РАН

Главная

Базы данных

Труды сотрудников ИФ СО РАН - результаты поиска

Вид поиска

Каталог книг и брошюр библиотеки ИФ СО РАН

Каталог журналов библиотеки ИФ СО РАН

Труды сотрудников ИФ СО РАН

Область поиска

в найденном

Найдено в других БД:

Каталог книг и брошюр библиотеки ИФ СО РАН (12)

Формат представления найденных документов:
полный	информационный	краткий

Отсортировать найденные документы по:
автору	заглавию	году издания	типу документа

Поисковый запрос: (<.>K=paramagnetic<.>)

Общее количество найденных документов : 87
Показаны документы с 1 по 10

1-10 11-20 21-30 31-40 41-50 51-60

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shapovalov V. V., Shapovalov V. A., Drokina T. V., Vorotynov A. M., Val'kov V. I.
Заглавие : Distribution of cobalt Co2+ ions in single crystals of spinel Li0.5Ga2.5O4
Колич.характеристики :6 с
Место публикации : Phys. Met. Metallogr. - 2024. - Vol. 125, Is. 1. - P.27-32. - ISSN 0031918X (ISSN), DOI 10.1134/S0031918X23602883. - ISSN 15556190 (eISSN)
Примечания : Cited References: 22
Аннотация: The distribution of Co2+ ions over sublattices and structurally nonequivalent positions in the unit cell of the crystal lattice of a single crystal of lithium gallium spinel Li0.5Ga2.5O4 is shown. This distribution determines the properties of both mono- and nanocrystalline substances. The distribution is obtained by a special technology and is manifested in the electron paramagnetic resonance (EPR) spectra. The distribution of Co2+ ions depends on the structural and magnetic nonequivalence. The structural and magnetic nonequivalence causes a multiminimum behavior of the crystal field potential in the unit cells of single crystals at the locations of Co2+ ions. The Co2+ ions are found in complexes with tetrahedral and octahedral oxygen ions. Three types of EPR spectra of Co2+ ions have been found and investigated. The Cotetr2+ spectrum is attributed to the Co2+ ion, which replaces the Ga3+ ion located in a tetrahedral oxygen environment. The spectrum of the Cooct2+ ion located in the crystal field with axial symmetry belongs to the Co2+ ion replacing the Li+ ion located in an octahedral oxygen environment. The spectrum of the Cooct2+ ion located in a low symmetry crystal field belongs to the Co2+ ion replacing the Ga3+ ion located in an octahedral oxygen environment. The nearest cationic environment of the ion creates rhombic distortions due to the different valence numbers of Li+ and Ga3+. The results of studying the angular dependences of the spectra show the presence of four and twelve magnetically nonequivalent positions in the unit cells.
Смотреть статью,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gokhfeld D. M., Semenov S. V., Nemtsev I. V., Yakimov I. S., Balaev D. A.
Заглавие : Magnetic ion substitution and peak effect in YBCO: the strange case of Y1–xGd xBa2Cu3O7–δ
Место публикации : J. Supercond. Novel Magn. - 2022. - Vol. 35, Is. 10. - P.2679-2687. - ISSN 15571939 (ISSN), DOI 10.1007/s10948-022-06317-2
Примечания : Cited References: 50. - This work was supported by the Russian Foundation for Basic Research and the Government of the Krasnoyarsk Territory, Krasnoyarsk Territorial Foundation for Support of Scientific and R&D Activities, project “Superconducting properties of YBCO incorporated by paramagnetic rare-earth elements” No. 20-42-240008
Аннотация: We present the results of a study of the superconducting and paramagnetic properties of polycrystalline Y1–xGdxBa2Cu3O7–δ samples. The critical current density and critical temperature of YBCO were weakly decreased by the Gd doping. A peak effect, which is a nonmonotonic dependence of the critical current density on magnetic field, was detected for all samples. The peak position shifted to higher magnetic fields with increasing Gd content. This behavior is opposite to the shift of the peak effect observed for other YBCO compounds doped by magnetic ions. This unusual behavior is apparently related to the realized granular structure instead of the type of doping ion. A correlation between the peak position and the granule size was found in the investigated samples and other polycrystalline YBCO compounds.
Смотреть статью,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Шаповалов В. В., Шаповалов В. А., Вальков В. И., Службин Ю. А., Дрокина, Тамара Васильевна, Воротынов, Александр Михайлович, Шавров В. Г.
Заглавие : Многоминимумность потенциала кристаллического поля в координационных материалах
Место публикации : Физ. техн. выс. давл. - 2022. - Т. 32, № 2. - С. 52-66. - ISSN 0868-5924
Примечания : Библиогр.: 30
Аннотация: Форма многоминимумного потенциала электрического кристаллического поля в нанокомплексе с магнитным ионом формируется ближайшим окружением иона и имеет несколько эквивалентных минимумов, которые соответствуют кристаллографическим осям комплекса. Для описания спектров электронного парамагнитного резонанса (ЭПР) магнитных ионов используется модель кристаллического поля и формализм спинового гамильтониана. Метод спинового гамильтониана позволяет описать спектр электронного парамагнитного резонанса. Задача теории - получение констант на основе определенной модели кристалла. Задача эксперимента - определение этих констант из вида спектра.The form of a multi-minimum potential of the electrical crystal field in a nanocomplex with a magnetic ion is formed by the nearest environment of the ion and characterized by several equivalent minima that are associated with crystallographic axes of the complex. To describe the spectra of electron paramagnetic resonance of magnetic ions (EPR), the model of crystal and the formalism of spin Hamiltonian is used. The method of spin Hamiltonian allows description of the spectrum of electron paramagnetic resonance. The theory is aimed to calculation of the constants within the frameworks of the determined model of the crystal. The experiment goal is evaluation of these constants on the basis of the spectrum shape.
Смотреть статью,
РИНЦ,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kudashev S. V., Kondrasenko A. A., Maiulev A. N., Babkin V. A., Belousova V. S., Andreev D. S., Zheltobryukhov V. F., Kuznetsova N. V.
Заглавие : Modification of polycaproamide composites based on 1H,1H,13H-rihydroperfluorotridecan-1-ol and montmorillonite
Место публикации : Fibre Chem. - 2022. - Vol. 53, Is. 5. - P.291-295. - ISSN 00150541 (ISSN), DOI 10.1007/s10692-022-10287-5
Примечания : Cited References: 24
Аннотация: Modification of polycaproamide by 1H,1H,13H-trihydroperfluorotridecan-1-ol immobilized on montmorillonite produced an F-containing polymer composite. The structure of the resulting composite was investigated using x-ray structure analysis and solid-state 19F NMR spectroscopy. The polymorphous composition of this heterochain polymer was shown to reorganize to enhance its thermal stability and diminish its flammability. Possible mechanisms for the stabilizing effect of the used modifier that were related to the involvement of organo-clay paramagnetic centers in the binding of macroradicals formed during thermal decomposition of macromolecular chains were discussed.
Смотреть статью,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gokhfeld D. M., Semenov S. V., Terentyev K. Yu., Yakimov I. S., Balaev D. A.
Заглавие : Interplay of magnetic and superconducting subsystems in Ho-doped YBCO
Коллективы : Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR); Government of the Krasnoyarsk Territory, Krasnoyarsk Territorial Foundation for Support of Scientific and R&D Activities, project "Superconducting properties of YBCO incorporated by paramagnetic rare-earth elements" [20-42-240008]
Место публикации : J. Supercond. Nov. Magn. - 2021. - Vol. 34. Is. 10. - P.2537-2543. - ISSN 1557-1939, DOI 10.1007/s10948-021-05954-3. - ISSN 1557-1947(eISSN)
Примечания : Cited References: 26. - This work was supported by the Russian Foundation for Basic Research and the Government of the Krasnoyarsk Territory, Krasnoyarsk Territorial Foundation for Support of Scientific and R&D Activities, project "Superconducting properties of YBCO incorporated by paramagnetic rare-earth elements" No. 20-42-240008
Предметные рубрики: TEMPERATURE
TRANSPORT
PEAK
DY
SUSCEPTIBILITY
TRANSITION
BEHAVIOR
Аннотация: Superconducting and paramagnetic contributions to the magnetization of polycrystalline Y1−xHoxBa2Cu3O7−δ samples were investigated. The superconductivity is responsible for a partial screening of magnetic ions from an external magnetic field and for a possible sinking of antiferromagnetic correlations between these ions. Magnetic moments of Ho ions influence on a peak effect induced by the order–disorder transition of the Abrikosov vortex lattice. The critical current density and the critical temperature of YBCO are not changed by the Ho doping.
Смотреть статью,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Lundin A. A., Zobov V. E.
Заглавие : Solid-state NMR free induction decay, simulated by the system of classical magnetic moments and quantum correlations
Коллективы : [AAAA-A19-119012890064-7]
Место публикации : Russ. J. Phys. Chem. B. - 2021. - Vol. 15, Is. 5. - P.839-847. - ISSN 1990-7931, DOI 10.1134/S1990793121050079. - ISSN 1990-7923(eISSN)
Примечания : Cited References: 34. - This study was carried out as part of state assignment 0082-2019-0001 (registration number AAAA-A19-119012890064-7)
Предметные рубрики: HIGH-TEMPERATURE DYNAMICS
HEISENBERG-MODEL
SPIN SIMULATIONS
SHAPE
Аннотация: In the past decade, nuclear magnetic resonance (NMR) has been actively used to study the basic principles of quantum computers. It is assumed that quantum correlations play a significant role in their performance. They exist at both low and high temperatures. At the same time, the time correlation functions of nuclear spin systems of solids determine the observed signals in traditional NMR implementations. The separation of such signals into quantum and classical components has not previously been carried out and will be performed in this study for the most important of the correlational functions observed in magnetic resonance: the free induction decay (FID).
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kazak N. V., Platunov M. S., Knyazev Yu. V., Molokeev M. S., Gorev M. V., Ovchinnikov S. G., Pchelkina Z. V., Gapontsev V. V., Streltsov S. V., Bartolome J., Arauzo A., Yumashev V. V., Gavrilkin S. Y., Wilhelm F., Rogalev A.
Заглавие : Spin state crossover in Co3BO5
Место публикации : Phys. Rev. B. - 2021. - Vol. 103, Is. 9. - Ст.094445. - ISSN 24699950 (ISSN), DOI 10.1103/PhysRevB.103.094445
Примечания : Cited References: 71. - We acknowledge many inspirational discussions on the topic of this paper with the late Natalia Ivanova and Leonard Bezmaternykh. The authors acknowledge A. Ney for allowing us to use the XANES spectrum of film. We are grateful to the Russian Foundation for Basic Research (Project No. 20-02-00559) and President Council on Grants (Project No. МК-2339.2020.2) for supporting this paper. This paper was carried out within the state assignment of the Russian Ministry of Science and High Education via program “Quantum”' (No. AAAA-A18-118020190095-4). We also acknowledge support by Russian Ministry of Education and Science via Contract No. 02.A03.21.0006. We acknowledge financial support from the Spanish Ministry of Economy, Industry and Competitiveness (MINECO, Grant No. MAT2017-83468-R) and from the regional Government of Aragon (E12-20R RASMIA project)
Аннотация: We have investigated the spin and oxidation states of Co in Co3BO5 using x-ray magnetic circular dichroism (XMCD) and dc magnetic susceptibility measurements. At low temperatures, XMCD experiments have been performed at the Co K-edge in Co3BO5 and Co2FeBO5 single crystals in the fully ferrimagnetically ordered phase. The Co (K-edge) XMCD signal is found to be related to the Co2+ magnetic sublattices in both compounds, providing strong experimental support for the low-spin (LS) Co3+ scenario. The paramagnetic susceptibility is highly anisotropic. An estimation of the effective magnetic moment in the temperature range 100–250 K correlates well with two Co2+ ions in the high-spin (HS) state and some orbital contribution, while Co3+ remains in the LS state. The crystal structure of the Co3BO5 single crystal has been solved in detail at the T range 296–703 K. The unit cell parameters and volume show anomalies at 500 and 700 K. The octahedral environment of the Co4 site strongly changes with heating. The generalized gradient approximation with Hubbard U correction calculations have revealed that, at low-temperatures, the system is insulating with a band gap of 1.4 eV, and the Co2+ ions are in the HS state, while Co3+ are in the LS state. At high temperatures (T 700 K), the charge ordering disappears, and the system becomes metallic with all Co ions in 3d7 electronic configuration and HS state.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Шаповалов В. В., Шаповалов В. А., Юрасов А. Н., Вальков В. И., Службин Ю. А., Дрокина, Тамара Васильевна, Воротынов, Александр Михайлович
Заглавие : Распределение магнитных нанозондов S-ионов марганца как результат структурной неэквивалентности в монокристалле шпинели Li0.5Ga2.5O4
Место публикации : Физ. техн. выс. давл. - 2021. - Т. 31, № 3. - С. 31-43. - ISSN 0868-5924
Примечания : Библиогр.: 28
Аннотация: Показано распределение ионов марганца Mn2+ по подрешеткам и структурно неэквивалентным положениям в элементарной ячейке кристаллической решетки монокристалла литий-галлиевой шпинели Li0.5Ga2.5O4. Такое распределение и самоорганизация элементарной ячейки монокристалла происходят в процессе его роста и определяют свойства как моно-, так и нанокристаллических веществ. Самоорганизация и распределение обеспечиваются специальной технологией и проявляются в спектрах электронного парамагнитного резонанса (ЭПР).The distribution of manganese ions Mn2+ over the sublattices and structurally nonequivalent positions within a unit cell of the lattice of single-crystal lithium-gallium spinel Li0.5Ga2.5O4 is demonstrated. The distribution and the self-organization of the unit cell of a single crystal progress in the course of the crystal growth and determine the properties of both single- and nanocrystal substances. Self-organization and distribution are provided by a special technology and affect the spectra of electron paramagnetic resonance (EPR).
Смотреть статью,
РИНЦ,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Vorotynov A. M., Pankrats A. I., Kolkov M. I.
Заглавие : EPR study of the single-ion magnetic anisotropy of the Fe3+ ion in a diamagnetic PbGaBO4 crystal
Коллективы : Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR); Government of the Krasnoyarsk Territory; Krasnoyarsk Regional Science Foundation [20-42-240006]
Место публикации : J. Exp. Theor. Phys. - 2021. - Vol. 133, Is. 5. - P.574-580. - ISSN 1063-7761, DOI 10.1134/S1063776121110054. - ISSN 1090-6509(eISSN)
Примечания : Cited References: 19. - This work was supported by the Russian Foundation for Basic Research, the Government of the Krasnoyarsk Territory, and the Krasnoyarsk Regional Science Foundation (project no. 20-42-240006 "Synthesis and study of oxide single crystals containing Pb2+ and Bi3+ with partial substitution in one of the subsystems: magnetic structures and magnetodielectric effect")
Предметные рубрики: ELECTRON PARAMAGNETIC RESONANCE
TRANSITION
SrTiO3
Аннотация: Crystals of a diamagnetic PbGaBO4 analog containing a small amount (about 0.5 at %) of Fe3+ ions are grown. The single-ion EPR spectra of Fe3+ in PbGa1-xFexBO4 single crystals are analyzed with allowance for a crystal structure. The existence of four magnetically nonequivalent positions of Fe3+ ions with different local anisotropy axis directions has been confirmed. The parameters of the spin Hamiltonian written in the approximation of the local orthorhombic symmetry of a paramagnetic center are determined. The values of single-ion anisotropy constants, which are unusually high for S ions, is shown to be caused by a strong distortion of the ligand environment of Fe3+ ions. The single-ion contribution to the energy of the total magnetic anisotropy of a magnetically concentrated PbGaBO4 crystal is estimated. Two-ion mechanisms of the Fe–Fe interaction anisotropy are assumed to play a dominant role in the formation of magnetic anisotropy in a magnetically concentrated crystal.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Semenov S. V., Gokhfel'd D. M., Terent'ev K. Yu., Balaev D. A.
Заглавие : Mechanisms of the magnetoresistance hysteresis in a granular HTS with the paramagnetic contribution by the example of HoBa2Cu3O7-δ
Коллективы : Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR); Government of the Krasnoyarsk krai; Krasnoyarsk Territorial Foundation for Support of Scientific and RD Activities [20-42-240008]
Место публикации : Phys. Solid State. - 2021. - Vol. 63, Is. 12. - P.1785-1794. - ISSN 1063-7834, DOI 10.1134/S1063783421100334. - ISSN 1090-6460(eISSN)
Примечания : Cited References: 72. - This study was supported by the Russian Foundation for Basic Research, the Government of the Krasnoyarsk krai, and the Krasnoyarsk Territorial Foundation for Support of Scientific and R&D Activities, project no. 20-42-240008 "Effect of introduction of paramagnetic ions of rare-earth elements on the superconducting properties of YBCO materials"
Предметные рубрики: HIGH-TEMPERATURE SUPERCONDUCTOR
MAGNETIC-FLUX COMPRESSION
Аннотация: The hysteretic behavior of magnetoresistance R(H) of the granular high-temperature superconductor (HTS) HoBa2Cu3O7 – δ has been investigated. The YBCO superconductors with a rare-earth element (Nd, Ho, Er, Sm, Yb, or Dy) with the magnetic moment in the yttrium site are characterized by a significant paramagnetic contribution to the total magnetization. The main goal of this study has been to establish the possible effect of this paramagnetic contribution on the magnetotransport properties, which are determined by tunneling of superconducting current carriers through the grain boundaries. An analysis of the results obtained basing on the concept of an effective field in the intergrain medium showed that the distribution of the magnetic induction lines from the paramagnetic moments is fundamentally different from that of the Meissner currents and Abrikosov vortices. The magnetic induction lines from the paramagnetic moments are not concentrated in the region of grain boundaries and therefore insignificantly affect the magnetotransport properties of a granular HTS. At the same time, the magnetic induction lines are strongly concentrated in the grain boundaries, which is caused by the Meissner currents and Abrikosov vortices, due to the features of their properties. Specifically, the magnetic flux compression determines the magnetotransport (in particular, the R(H) hysteresis) properties of granular HTSs, including 1–2–3 ones, with a rare-earth ion with the magnetic moment.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие