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

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Каталог книг и брошюр библиотеки ИФ СО РАН

Каталог журналов библиотеки ИФ СО РАН

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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gan’shina, Elena A., Granovsky, Alexandr B., Garshin, Vladimir V., Pripechenkov, Ilya M., Sitnikov, Alexandr V., Volochaev M. N., Ryl’kov, Vladimir V., Nikolaev, Sergey N.
Заглавие : Magneto-optical spectroscopy of nanocomposites (CoFeZr)x(Al2O3)100-x
Место публикации : SPIN. - 2023. - Vol. 13, Is. 1. - Ст.2340006. - ISSN 20103247 (ISSN), DOI 10.1142/S2010324723400064. - ISSN 20103255 (eISSN)
Примечания : Cited References: 17. - This work was supported in part by the Russian Foundation for Basic Research under Grant 22-29-00392. Magnetic and MO studies were performed using equipment purchased at the expense of the MSU The authors thank the Krasnoyarsk Regional Center of Research Equipment of Federal Research Center “Krasnoyarsk Science Center SB RAS” for assistance
Аннотация: We present results of magneto-optical investigations of (CoFeZr)x(Al2O3)100-x film nanocomposites in transverse Kerr effect (TKE) geometry in the spectral range 0.5-4.0eV and magnetic field up to 3.0kOe. Nanocomposites were deposited onto a glass-ceramic substrate by ion-beam sputtering. The TKE response at room temperature strongly depends on the wavelength of light, applied magnetic field H and the volume metallic fraction. From the analysis of the field dependences of TKE at different wavelengths, it follows that in the as-deposited samples, the interaction between nanoparticles at x30at.% is small and the nanocomposite is an ensemble of superparamagnetic particles; as x increases to 32at.%, a superspinglass-type state arises, then, in the vicinity of 34at.%, along with individual superparamagnetic particles, superferromagnetic regions appear. Long-range ferromagnetic order arises at concentrations x less than the percolation threshold for conductivity xper
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Vazhenina I. G., Stolyar S. V., Tyumentsev A. V., Volochaev M. N., Iskhakov R. S., Komogortsev S. V., Pyankov V. F., Nikolaeva E. D.
Заглавие : Study of magnetic iron oxide nanoparticles coated with silicon oxide by ferromagnetic method
Колич.характеристики :5 с
Коллективы : Nanophysics and Nanoelectronics, International Symposium
Место публикации : Phys. Solid State. - 2023. - Vol. 65, Is. 6. - P.884-888. - ISSN 10637834 (ISSN), DOI 10.21883/PSS.2023.06.56095.01H. - ISSN 10906460 (eISSN)
Примечания : Cited References: 20. - The study was supported by grant No. 22-14-20020 provided by the Russian Science Foundation, Krasnoyarsk Regional Science Foundation
Аннотация: agnetic nanoparticles of magnetite with a size of ~8 nm synthesized with a different type of coating were studied by ferromagnetic resonance in the temperature range from 7 to 300 K. The features of the experimental temperature dependences of the parameters of the ferromagnetic resonance curve (the magnitude of the resonant field, line width and intensity) and their approximation allowed us to estimate the values of characteristic temperatures. Firstly, the value of the Vervey temperature and the dependence of its value on the type of coating were determined. Secondly, the temperature of transition of nanoparticles to the superparamagnetic state (blocking temperature) and the temperature range within which the magnetic structure of the outer shell of the magnetic nanoparticle is in the spin glass state are established.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Knyazev Yu. V., Balaev D. A., Stolyar S. V., Krasikov A. A., Bayukov O. A., Volochaev M. N., Yaroslavtsev R. N., Ladygina V. P., Velikanov D. A., Iskhakov R. S.
Заглавие : Interparticle magnetic interactions in synthetic ferrihydrite: Mossbauer spectroscopy and magnetometry study of the dynamic and static manifestations
Место публикации : J. Alloys Compd. - 2022. - Vol. 889. - Ст.161623. - ISSN 09258388 (ISSN), DOI 10.1016/j.jallcom.2021.161623
Примечания : Cited References: 84. - This study was supported by the Russian Foundation for Basic Research, the Government of the Krasnoyarsk Territory, and the Krasnoyarsk Territorial Foundation for Support of Scientific and R&D Activities, project no. 19–42–240012 R-A “Magnetic Resonance in Ferrihydrite Nanoparticles: Effects Related to the Core-Shell Structure”
Аннотация: Samples of synthetic ferrihydrite with an average nanoparticle size of 2.7 nm have been examined by magnetometry and Mossbauer spectroscopy. Ferrihydrite is characterized by the antiferromagnetic interactions between the magnetic moments of iron atoms. In ferrihydrite nanoparticles, as in any other antiferromagnetic ones, structural defects induce the formation of an uncompensated magnetic moment, which determines the magnetic properties typical of single-domain ferro- and ferrimagnetic particles. The manifestation of the magnetic interactions between ferrihydrite nanoparticles in the magnetic properties of the material and in the temperature evolution of Mossbauer spectra has been in focus. The results obtained on synthetic ferrihydrite have been compared with the data for the biogenic ferrihydrite sample with a similar average size of particles surrounded by a polysaccharide shell, which weakens and screens the interparticle magnetic interactions. A clear manifestation of the effect of the interparticle magnetic interactions on the transition to the blocked state is the presence of a significant contribution of the relaxation component in the Mossbauer spectra at temperatures of the transition from the superparamagnetic to blocked state. The temperature dependence of the particle relaxation time obtained from the Mossbauer spectra points out the collective effect of freezing of the magnetic moments of particles due to the magnetic interactions between them.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Balaev D. A., Stolyar S. V., Knyazev Yu. V., Yaroslavtsev R. N., Pankrats A. I., Vorotynov A. M., Krasikov A. A., Velikanov D. A., Bayukov O. A., Ladygina V. P., Iskhakov R. S.
Заглавие : Role of the surface effects and interparticle magnetic interactions in the temperature evolution of magnetic resonance spectra of ferrihydrite nanoparticle ensembles
Место публикации : Results Phys. - 2022. - Vol. 35. - Ст.105340. - ISSN 22113797 (ISSN), DOI 10.1016/j.rinp.2022.105340
Примечания : Cited References: 119. - Authors thank to A.D. Balaev, S.V. Komogortsev for fruitful discussions and M.N. Volochaev for TEM studies. The TEM study and measurements of X-band FMR spectra were carried out on the equipment of the Krasnoyarsk Territorial Center for Collective Use, Krasnoyarsk Scientific Center, Siberian Branch, Russian Academy of Sciences. This study was supported by the Russian Science Foundation, project no. 21-72-00025 (https://rscf.ru/project/21-72-00025/) "Tuning the Magnetic Properties of Ultrafine Biocompatible Ferrihydrite Nanoparticles through Interparticle Interactions"
Аннотация: Ferrihydrite is characterized by the antiferromagnetic ordering and, in ferrihydrite nanoparticles, as in nanoparticles of any antiferromagnetic material, an uncompensated magnetic moment is formed. We report on the investigations of ferrihydrite powder systems with an average particle size of ∼ 2.5 nm obtained (i) as a product of the vital activity of bacteria (sample FH-bact) and (ii) by a chemical method (sample FH-chem). In the first approximation, these samples can be considered to be identical. However, in sample FH-chem, particles contact directly, while in sample FH-bact, they have organic shells; therefore, the interparticle magnetic interactions in these samples have different degrees. The main goal of this work has been to establish the effects of the interparticle magnetic interactions and individual characteristics of ferrihydrite nanoparticles on ferromagnetic resonance (FMR) spectra. The FMR spectra have been measured at different (9.4–75 GHz) frequencies in a wide temperature range. It has been found that, at low temperatures, the field-frequency dependence ν(HR) of the investigated systems has a gap ν/γ = HR + HA, where HR is the resonance field and HA is the induced anisotropy, which decreases with increasing temperature. To estimate a degree of the effect of interparticle interactions on the results obtained and to correctly determine the temperature range of the superparamagnetic (or blocked) state, the static magnetic measurement and Mössbauer spectroscopy data have been obtained and analyzed. It has been shown that the most striking feature of the FMR spectra - a gap in the field-frequency dependences - is a manifestation of individual characteristics of ferrihydrite nanoparticles. The induced anisotropy is caused by freezing of a subsystem of surface spins and its coupling with the particle core, which is observed in both samples at a temperature of ∼80 K. The temperature range (below 80 K) in which the gap exists corresponds to the blocked state in the FMR technique. In sample FH-bact, the ratio between the FMR parameters HA and linewidth ΔH obeys the standard expression HA ∼ (ΔH)3. In sample FH-chem, however, the interparticle magnetic interactions dramatically affect the behavior of parameters of the FMR spectra, which change nonmonotonically upon temperature variation. This fact is attributed to the collective freezing of the magnetic moments of particles under the conditions of sufficiently strong interactions, which follows from the temperature dependence of the particle magnetic moment relaxation time determined from the Mössbauer spectroscopy and static magnetometry data obtained in weak magnetic fields.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Stolyar S. V., Komogortsev S. V., Gorbenko A. S., Knyazev Yu. V., Yaroslavtsev R. N., Olkhovskiy I. A., Neznakhin D. S., Tyumentseva A. V., Bayukov O. A., Iskhakov R. S.
Заглавие : Maghemite nanoparticles for DNA extraction: Performance and blocking temperature
Место публикации : J. Supercond. Novel Magn. - 2022. - Vol. 35, Is. 7. - P.1929-1936. - ISSN 15571939 (ISSN), DOI 10.1007/s10948-022-06233-5
Примечания : Cited References: 33. - This work was supported by Russian Foundation for Basic Research, Government of Krasnoyarsk Territory, Krasnoyarsk Region Science and Technology Support Fund, with research projects no. 20–42-242902. We are grateful to the Center of Collective Use of FRC KSC SB RAS for the provided equipment
Аннотация: Iron oxide nanoparticles coated with polyethylene glycol were synthesized by coprecipitation for use in the magnetic separation of DNA (deoxyribonucleic acid). The blocking temperature of nanoparticles was studied by the methods of Mossbauer spectroscopy, ferromagnetic resonance, and using magnetometric measurements. The blocking temperature calculated from the temperature dependence of the coercive force was ~ 200 K. The calculation of the blocking temperature from the relaxation time obtained using Mossbauer spectroscopy gave a value of ~ 450 K. The blocking temperature obtained using ferromagnetic resonance was ~ 910 K. The relationship between the obtained blocking temperatures is in good agreement with the Neel-Brown formula. The constants of effective and surface anisotropy were determined by the method of ferromagnetic resonance. Isolation of DNA from blood using prepared particles and separation in a permanent magnet field revealed sufficient productivity, high speed, and the “chemical delicacy” of this approach.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Knyazev Yu. V., Balaev D. A., Stolyar S. V., Bayukov O. A., Yaroslavtsev R. N., Ladygina V. P., Velikanov D. A., Iskhakov R. S.
Заглавие : Magnetic anisotropy and core-shell structure origin of the biogenic ferrihydrite nanoparticles
Место публикации : J. Alloys Compd. - 2021. - Vol. 851. - Ст.156753. - ISSN 09258388 (ISSN), DOI 10.1016/j.jallcom.2020.156753
Примечания : Cited References: 82. - The electron microscopy study was carried out on the equipment of the Krasnoyarsk Territorial Center for Collective Use, Krasnoyarsk Scientific Center, Siberian Branch, Russian Academy of Sciences. This study was supported by the Russian Foundation for Basic Research, the Government of the Krasnoyarsk Territory, and the Krasnoyarsk Territorial Foundation for Support of Scientific and R & D Activities, project no. 19-42-240012 p-a “Magnetic Resonance in Ferrihydrite Nanoparticles: Effects Related to the Core–Shell Structure”
Аннотация: Ferrihydrite is a low-crystalline nanoscale matter. The uncompensated magnetic moment of the ferrihydrite caused by the antiferromagnetic ordering of the magnetic moments of iron atoms and leads to the magnetic properties very similar to those of ferro- and ferrimagnetic nanoparticles. In this study, we investigated the biogenic ferrihydrite nanoparticles with the narrow size distribution and an average diameter of ≈2 nm obtained by the bacteria life cycle. The features caused by the surface effects and the inhomogeneous structure of ferrihydrite have been examined in the temperature range of 4–300 K using Mossbauer spectroscopy and magnetometry. Based on the Mossbauer data, we identified the superparamagnetic blocking temperature at the temperature of 30 K for the largest ferryhidrite particles. We established that the exceptional magnetic anisotropy of ferrihydrite (KV=1.2∙105 erg/cm3 and KS=0.1 erg/cm2) is reached because of the highly developed ferrihydrite nanoparticles’ surface. According to the Mossbauer data, we propose a core-shell structural model of the biogenic ferrihydrite particles. We found that the size of the dense core depends on the particle size. The well-crystallized core is formed only for nanoparticles larger than ≈2 nm, whereas smaller particles consist entirely of a matter with a lower density of iron atoms.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Balaev D. A., Poperechny I. S., Krasikov A. A., Semenov S. V., Popkov S. I., Knyazev Yu. V., Kirillov V. L., Yakushkin S. S., Martyanov O. N., Raikher Y. L.
Заглавие : Dynamic remagnetisation of CoFe2O4 nanoparticles: thermal fluctuational thawing of anisotropy
Коллективы : [AAAA-A17-117103050081-1]; [AAAAA20-120020690030-5]
Место публикации : J. Phys. D. - 2021. - Vol. 54, Is. 27. - Ст.275003. - ISSN 0022-3727, DOI 10.1088/1361-6463/abf371. - ISSN 1361-6463(eISSN)
Примечания : Cited References: 63. - Experimental measurements were supported by Project No. AAAA-A17-117103050081-1. I S P and Yu L R acknowledge the support of ICMM in the framework of topical task AAAAA20-120020690030-5. The numerical calculations were performed on the Uran supercomputer (Ural Branch, Russian Academy of Sciences, Ekaterinburg)
Предметные рубрики: COBALT-FERRITE NANOPARTICLES
MAGNETIC-PROPERTIES
SIZE
COERCIVITY
Аннотация: We report a study of the magnetodynamics of cobalt ferrite (CoFe2O4) nanoparticles with an average diameter of ~6 nm. Hysteresis loops were measured under quasi-static conditions and in pulse fields with amplitudes H0 of up to 130 kOe and for durations τP of 8 and 16 ms. The growth of coercivity Hc observed with an increase in the magnetic field variation rate dH/dt (determined by the values of H0 and τP) and the reduction of Hc with temperature is ascribed to the superparamagnetic effect. The proposed theoretical model explains the observed dependences fairly well. Notably, the effective magnetic anisotropy constant obtained exceeds the value for bulk crystals and might be indicative of the contribution of surface magnetic anisotropy.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Balaev D. A., Krasikov A. A., Popkov S. I., Semenov S. V., Volochaev M. N., Velikanov D. A., Kirillov V. L., Martyanov O. N.
Заглавие : Uncompensated magnetic moment and surface and size effects in few-nanometer antiferromagnetic NiO particles
Место публикации : J. Magn. Magn. Mater. - 2021. - Vol. 539. - Ст.168343. - ISSN 03048853 (ISSN), DOI 10.1016/j.jmmm.2021.168343
Примечания : Cited References: 98. - The TEM study was carried out on the equipment of the Krasnoyarsk Territorial Center for Collective Use, Krasnoyarsk Scientific Center, Siberian Branch, Russian Academy of Sciences
Аннотация: The analysis of the M(H) magnetization curves of antiferromagnetic nanoparticles yields information about magnetic subsystems formed in these objects, which are characterized by a large fraction of surface atoms. However, in the conventionally investigated experimental magnetic field range of up to 60–90 kOe, this analysis often faces the ambiguity of distinguishing the Langevin function-simulated contribution of uncompensated magnetic moments μun of particles against the background of a linear-in-field dependence (the antiferromagnetic susceptibility and other contributions). Here, this problem has been solved using a pulsed technique, which makes it possible to significantly broaden the range of external fields in which the μun contribution approaches the saturation. Nanoparticles of a typical NiO antiferromagnet with an average size of d ~ 4.5 nm have been investigated. Based on the thorough examination of the M(H) magnetization curves measured in pulsed fields of up to 250 kOe, a model of the magnetic state of NiO nanoparticles of such a small size has been proposed. The average moment is ~130 μB (μB is the Bohr magneton) per particle, which corresponds to 60–70 decompensated spins of nickel atoms localized, according to the Néel hypothesis (μun ~ d3/2), both on the surface and in the bulk of a particle. A part of the surface spins unrelated to the antiferromagnetic core form another subsystem, which behaves as free paramagnetic atoms. Along with the antiferromagnetic core, an additional linear-in-field contribution has been detected, which is apparently related to superantiferromagnetism, i.e., the size effect inherent to small antiferromagnetic particles.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Petrov D. A., Ivantsov R. D., Zharkov S. M., Velikanov D. A., Molokeev M. S., Lin C. -R., Tso C. -T., Hsu H. -S., Tseng Y. -T., Lin E. -S., Edelman I. S.
Заглавие : Magnetic and magneto-optical properties of Fe3O4 nanoparticles modified with Ag
Место публикации : J. Magn. Magn. Mater. - 2020. - Vol. 493. - Ст.165692. - ISSN 03048853 (ISSN), DOI 10.1016/j.jmmm.2019.165692
Примечания : Cited References: 45. - The reported study was funded by Russian Foundation for Basic Research, Government of Krasnoyarsk Territory, Krasnoyarsk Regional Fund of Science to the research project № 18-42-243021 and by Joint Research Project of Russian Foundation for Basic Research № 19-52-52002 and Ministry of Science and Technology, Taiwan MOST № 108-2923-M-153-001-MY3 and № 106-2112-M-153-001-MY3.
Аннотация: Effect of Ag inclusions on magnetic properties and magnetic circular dichroism (MCD) of Fe3O4 nanoparticles (NPs) in the mixed system of Fe3O4 and Ag NPs in dependence on the relative concentration of the components is presented. The samples were synthesized by the thermal decomposition of the mixture of constant concentration of Fe(NO3)3·9H2O and varied concentration of AgNO3. The synthesized powdered samples consisted of Fe3O4 and Ag NPs located very close with each other, and in the most cases the Fe3O4 NPs were bordered with the Ag nanocrystals. The Ag introducing in the samples does not effect, practically, in the Fe3O4 NPs morphology and size distribution. At the same time, Ag NPs in the powdered samples cause a decrease in the Fe3O4 NPs magnetization and shift of the blocking temperature to lower temperatures, both approximately proportional to the Ag concentration. Most significant changes are revealed in the MCD spectra in the energy region of 1.2–2.2 eV. We have discussed the influence of the Ag NPs on the MCD spectra features in terms of the charge-transfer electron transitions. © 2019 Elsevier B.V.
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10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Yurkin G. Yu., Patrin G. S., Yarikov S. A.
Заглавие : Magnetic Properties of Fe1-xCoxSi Single Crystals at Low Co Impurity Concentrations
Место публикации : J. Sib. Fed. Univ. Math. Phys. - 2019. - Vol. 12, Is. 6. - P.756-771. - ISSN 1997-1397, DOI 10.17516/1997-1397-2019-12-1-1-6; Журн. СФУ. Матем. и физика. - ISSN 2313-6022 (eISSN)
Примечания : Cited References: 17
Аннотация: Velocity of bulk acoustic waves in base and rotated cuts have been measured by the ultrasonic pulse-echo method and values of CE ijkl and eijk in single crystals YAl3(BO3)4 have been calculated. The value of dijk piezoelectric modulus of these single crystals have been determined by quasistatic measurements, and εσ ij dielectric constants have been determined by the flat capacitor method. Experimental values of material constants have been applied for the study of Magnetostatic properties of FeSi and Fe0;98Co0;02Si single crystals have been studied. It has been found that the temperature and field dependences of the magnetization of monocrystal FeSi are strongly affected by introduction of a small amount of Co (2 %). A description of the results were provided by a model accounting for the formation of superparamagnetic iron clusters, as well as Fe-Co complexes. It is assumed that Fe-Co complexes form a ferromagnetic phase, which is approximately 0.6% of the Fe0;98Co0;02Si sample weightВ работе представлено исследование магнитостатических характеристик образцов FeSi и Fe0;98Co0;02Si. Обнаружено, что внесение небольшого количества примести Co (2 %) значительно влияет на температурные и полевые зависимости намагниченности монокристалла FeSi. Результаты обрабобтаны в рамках модели, учетывающей образование суперпарамагнитных кластеров железа, а также комплексов Fe-Co. Предполагается, что комплексы Fe-Co образуют ферромагнитную фазу, которая составляет примерно 0,6 % от массы образца Fe0;98Co0;02Si.
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