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1.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Aksenov S. V., Val'kov V. V., Ulanov E. A.
Заглавие : A Fano resonance in transport characteristics of 1D atomic spin structures
Коллективы : Институт теоретической физики им. Л. Д. Ландау РАН, Институт физики твердого тела РАН, "Mesoscopic and Strongly Correlated Electron Systems", conference (6; 2012 ; июнь ; 17-23; Черноголовка, Моск. обл.)
Место публикации : Book of abstracts of Advances Research Workshop "Meso–2012". - 2012. - P.37
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2.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kovaleva E. A., Kuzubov A. A., Avramov P. V., Kholtobina A. S., Kuklin A. V., Tomilin F. N., Sorokin P. B.
Заглавие : A key role of tensile strain and surface termination in formation and properties of La0.7Sr0.3MnO3 composites with carbon nanotubes
Место публикации : Comput. Mater. Sci.: Elsevier, 2017. - Vol. 139. - P.125-131. - ISSN 09270256 (ISSN), DOI 10.1016/j.commatsci.2017.07.021
Примечания : Cited References: 39. - This work was supported by National Research Foundation of Republic of Korea under Grant No. NRF-2017R1A2B4004440 and the government contract of the Ministry of Education and Science of the Russian Federation to Siberian Federal University (Grant No. 16.1455.2017/PCh). The authors would like to thank Joint Supercomputer Center of RAS, Moscow; Center of Equipment for Joint Use of Siberian Federal University, Krasnoyarsk; and Information Technology Centre, Novosibirsk State University for providing the access to their supercomputers. P.B.S gratefully acknowledges the financial supports of the Ministry of Education and Science of the Russian Federation in the framework of Increase Competitiveness Program of NUST «MISiS» (No. К2-2017-001) and RFBR, according to the research project No. 16-32-60138 mol_a_dk. E.A. Kovaleva would also like to acknowledge the program of the President of Russian Federation for Leading Scientific Schools Support (Grant No. 2016 NSh-7559.2016.2).
Ключевые слова (''Своб.индексиров.''): carbon nanotubes--lsmo--interface--spin polarization
Аннотация: Atomic and electronic structure of LSMO-based composites with carbon nanotubes were studied by means of density functional theory with respect to the termination of LSMO surface. The deformation of the tubes caused by the lattice mismatch with the substrate leads to a major change in their electronic structure. The surface terminated with Mn-O layer provides much stronger interaction with carbon nanotubes than Sr-O terminated one does. The interaction with transition metal atoms is essential for spin polarization of the nanotube while no spin injection was observed for Sr-O-supported tubes. © 2017 Elsevier B.V.
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3.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Fransson J., Sandalov I., Eriksson O.
Заглавие : A perfect spin-filter quantum dot system
Место публикации : J. Phys.: Condens. Matter: IOP PUBLISHING LTD, 2004. - Vol. 16, Is. 16. - P.L249-L254. - ISSN 0953-8984, DOI 10.1088/0953-8984/16/16/L03
Примечания : Cited References: 39
Предметные рубрики: NARROW ENERGY BANDS
ELECTRON CORRELATIONS
MAGNETIC-FIELD
MAGNETOTRANSPORT
CONDUCTANCE
RESISTANCE
BARRIER
FORMULA
VALVE
LIMIT
Ключевые слова (''Своб.индексиров.''): electric potential--electron tunneling--magnetic couplings--magnetic fields--magnetic filters--transport properties--electron correlations--magnetic contacts--source-drain voltage--spin projections--semiconductor quantum dots
Аннотация: The discovery of a novel effect in the transport through a QD spin-dependently coupled to magnetic contacts is reported. For a finite range of source-drain voltages the spin projections of the current cancel exactly, resulting in a completely suppressed output current. The spin down current behaves as one normally expects whereas the spin up current becomes negative. As the source-drain voltage is increased the spin up current eventually becomes positive. Thus, tuning the source-drain voltage such that the spin up current vanishes will result in a perfect spin filter.
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4.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gekht R. S., Bondarenko I. N.
Заглавие : A quantum spin liquid in a two-layer triangular antiferromagnet
Место публикации : J. Exp. Theor. Phys.: AMER INST PHYSICS, 2005. - Vol. 101, Is. 5. - P868-880. - ISSN 1063-7761, DOI 10.1134/1.2149066
Примечания : Cited References: 43
Предметные рубрики: ONE-DIMENSIONAL ANTIFERROMAGNETS
DIMER GROUND-STATE
MEAN-FIELD THEORY
HEISENBERG-ANTIFERROMAGNET
SYSTEM SRCU2(BO3)(2)
PHASE-TRANSITION
GAP
FLUCTUATIONS
EXCITATIONS
LATTICE
Ключевые слова (''Своб.индексиров.''): antiferromagnetic materials--magnetic fields--magnetization--phase diagrams--spectrum analysis--thermodynamics--analogous systems--square lattices--thermodynamic quantities--two-layer triangular antiferromagnets--quantum theory
Аннотация: The possibility of implementing a quantum-spin-liquid-type state in a two-layer triangular spin-1/2 antiferromagnet at T = 0 is investigated. The ratio of intra- to interlayer exchange constants (j) is found under which a transition from the classical state with 120 degrees triangular order to a quantum state with zero magnetization per site occurs; in this case, the spins of adjacent layers form singlets that are separated from triplet excitations by an energy gap. Compared with an analogous system with the square lattice, the range of j in which the classical ordered state is realized turns out to be an order of magnitude smaller due to the effects of frustration; in this case, the behavior of thermodynamic quantities is analogous, on the whole, to that in two-layer square lattices; a difference manifests itself in the behavior of the gap in the spectrum of quasiparticles in an external magnetic field h. For small fields h, a j-h phase diagram is constructed that determines the domains in which the 120 degrees and the singlet phases exist. It is established that, in the neighborhood of the second-order phase transition, the contribution, to the thermodynamic quantities, of longitudinal spin fluctuations, which are disregarded in the spin-wave description, is comparable to the contribution of transverse fluctuations. (c) 2005 Pleiades Publishing, Inc.
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5.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zhandun V. S., Nemtsev A. V.
Заглавие : Ab initio study of the magnetic, optical and electronic properties of spinel Co3O4 within DFT and GW approaches
Место публикации : J. Magn. Magn. Mater. - 2020. - Vol. 499. - Ст.166306. - ISSN 0304-8853, DOI 10.1016/j.jmmm.2019.166306. - ISSN 1873-4766 (eISSN)
Примечания : Cited References: 65. - The reported study was funded by Russian Foundation for Basic Research, Government of Krasnoyarsk Territory, Krasnoyarsk Regional Fund of Science to the research project № 18-42-243019: «First-principles studies of the polarization, magnetic, electronic, and magnetoelectric properties of functional compounds with a spinel structure containing 3d and 4f ions». The calculations were performed with the computer resources of “Complex modeling and data processing research installations of mega-class ”SRC“ Kurchatovsky Institute” (http://ckp.urcki.ru).
Аннотация: The spinel cobalt oxide Co3O4 is an antiferromagnetic semiconductor containing two non-equivalent Co2+ and Co3+ cobalt ions with different local environments and different magnetic moments. We have performed ab initio study and comparison of the electronic, magnetic and optical properties of Co3O4 within GGA, GGA + U, and G0W0 approximations. GGA correctly predicts Co3O4 to be a semiconductor, but severely underestimates the bandgap. G0W0 approximations increase the bandgap indicating a better description of the cobalt localized d-states. The spectral weights of the bands near Fermi energy are about 0.5. Ab initio calculations confirm that the low-spin state of Co3+ ion arises due to the local environment and the crystal effect field. The investigation of the pressure dependencies of magnetic properties revealed the appearance of Co3+ ion abrupt transition from low-spin state to high-spin state under tensile pressure. This allows manipulating the spin state of Co3+ ions through the pressure or strain.
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6.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ovchinnikov S. G.
Заглавие : Analysis of the sequence of insulator-metal phase transitions at high pressure in systems with spin crossovers
Место публикации : J. Experim. Theor. Phys. - 2013. - Vol. 116, Is. 1. - P.123-127. - DOI 10.1134/S1063776113010111
Примечания : Cited References: 18. - This study was supported in part by the Russian Foundation for Basic Research (project. no. 100200251), the Presidential Program of Support for Lead ing Scientific Schools in Russia (project no. NSh 1044.2012.2), the Presidium of the Russian Academy of Sciences (program no. 2.16), and the Siberian Branch of the Russian Academy of Sciences (program nos. 96 and 97), and the Siberian Federal University (project no. F11)
Аннотация: Possible variants of the Mott–Hubbard phase transitions at high pressure in systems with spin cross-overs are considered. Owing to the universal character of the dependence of the effective Hubbard parameterUeff(dn) on the average number of d electrons, which is determined by the presence of spin crossovers, cascadesof insulator–metal–insulator phase transitions in systems with d3, d6, and d8 configurations become possible.Moreover, the systems with d6 configuration can exhibit transitions from a metal in the absence of external pres-sure to an insulator at high pressure.
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7.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Val'kov V. V., Aksenov S. V.
Заглавие : Andreev bound states and the Josephson current through a spin dimeric structur
Коллективы : "Spin Waves", International Simposium, Физико-технический институт им. А.Ф. Иоффе РАН
Место публикации : Spin Waves 2015, Int. Symp.: abstracts. - СПб., 2015. - P.126
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8.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Lukyanenko A. V., Gustaitsev A. O., Smolyakov D. A., Tarasov A. S., Varnakov S. N., Volkov N. V.
Заглавие : Anisotropy of the magnetoimpedance in hybrid hetero structure FeNi/SiO2/p-Si
Коллективы : "Spin physics, spin chemistry, and spin technology", Internnational conference, Физико-технический институт им. А.Ф. Иоффе РАН, Казанский физико-технический институт им. Е. К. Завойского Казанского научного центра РАН, "Инно-мир", центр межрегионального инновационного развития
Место публикации : Int. conf. "Spin physics, spin chem., and spin technol.". - 2015. - P.111
Примечания : This study was supported by the Russian Foundation for Basic Research, projects nos. 14-02-31156 and 14-02-00234, and the Russian Ministry of Education and Science, project no. 02.G25.31.0043
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9.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aplesnin S. S., Piskunova N. I.
Заглавие : Anomalies in magnetoresistance and in the bulk modulus for ferromagnetics with four-spin exchange interaction on the Kondo lattice
Место публикации : J. Phys.: Condens. Matter: IOP PUBLISHING LTD, 2006. - Vol. 18, Is. 29. - P.6859-6868. - ISSN 0953-8984, DOI 10.1088/0953-8984/18/29/023
Примечания : Cited References: 29
Предметные рубрики: MIXED-VALENCE MANGANITES
PHASE-SEPARATION
LA1-XSRXMNO3
BEHAVIOR
PECULIARITIES
TRANSITION
Ключевые слова (''Своб.индексиров.''): elastic moduli--electric resistance--ferromagnetism--function evaluation--paramagnetism--transceivers--adiabatic approximation--kondo lattice--paramagnetic state--ring exchange--magnetoresistance
Аннотация: The temperature dependence of resistivity and the bulk modulus are calculated on the Kondo lattice, with ring exchange between localized spins, using the spin-polaron and adiabatic approximation. Peak and zero values of the bulk modulus as functions of temperature and concentration are determined below the temperature of the transition to the paramagnetic state. The effects of the nearest order between transverse spin components and a value of the ring exchange between localized spins on magnetoresistivity are estimated.
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10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Dudnikov V. A., Orlov Yu. S., Kazak N. V., Platunov M. S., Ovchinnikov S. G.
Заглавие : Anomalies of the electronic structure and physical properties of rare-earth cobaltites near spin crossover
Место публикации : JETP Letters. - 2016. - Vol. 104, Is. 8. - P.588-600. - ISSN 00213640 (ISSN), DOI 10.1134/S002136401620011X
Примечания : Cited References: 101. - We are grateful to our colleagues A. Anshits, N. Perov, L. Solov’ev, S. Vereshchagin, S. Gavrilkin, V. Voronov, K. Shaikhutdinov, A. Rogalev, and M.V. Gorev for the fruitful collaboration in the studies of cobaltites for many years. This work was supported by the Council of the President of the Russian Federation for Support of Young Scientists and Leading Scientific Schools (project nos. NSh-7559.2016.2, SP-1844.2016.1, and SP-938.2015.5), by the Foundation for Support of Innovations (program UMNIK), by the Russian Foundation for Basic Research (project nos. 16-02-00507, 16-02-00098, 16-32-60049-mol-a-dk, and 16-32-00206_mol-a), and jointly by the Russian Foundation for Basic Research and the Krasnoyarsk Territorial Science Foundation (project nos. 16-42-240413, 16-43-240505, and 16-42-240470).
Аннотация: The features of the characteristics of LnCoO3 cobaltites, where Ln is a rare-earth element, are discussed. Both experiment and theory demonstrate that their essentials are related to the low-spin ground state of cobalt ions. The thermally induced occupation of the excited high-spin state gives rise to peaks in the magnetic susceptibility, specific heat, and thermal expansion, as well as to a smooth insulator–metal transition. The analysis is based both on the data from the current literature concerning LaCoO3 and in many aspects on our own studies of GdCoO3 and La1?xGdxCoO3 solid solutions. © 2016, Pleiades Publishing, Inc.
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11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gavriliuk A. G., Struzhkin V. V., Lyubutin I. S., Ovchinnikov S. G., Hu M. Y., Chow P.
Заглавие : Another mechanism for the insulator-metal transition observed in Mott insulators
Место публикации : Phys. Rev. B: AMER PHYSICAL SOC, 2008. - Vol. 77, Is. 15. - Ст.155112. - ISSN 1098-0121, DOI 10.1103/PhysRevB.77.155112
Примечания : Cited References: 26
Предметные рубрики: ELECTRONIC-STRUCTURE
SPIN TRANSITION
HIGH-PRESSURES
GDFE3(BO3)(4)
Аннотация: The two widely accepted mechanisms of the insulator-metal Mott-Hubbard transitions which have been considered up until now are driven by the band-filling or bandwidth effects. We found a different mechanism of the Mott-Hubbard insulator-metal transition, which is controlled instead by the changes in the Mott-Hubbard energy U. In contrast to the changes in the bandwidth W in the "bandwidth control" scenario or to the variations of the band-filling n parameter in the "band-filling" scenario, a dramatic decrease in the Mott-Hubbard energy U plays the key role in this mechanism. We have experimentally observed this type of the insulator metal transition in the transition metal oxide BiFeO(3). The decrease in the Mott-Hubbard energy is caused by the high-spin-low-spin crossover in the electronic d shell of 3d transition metal ion Fe(3+) with d(5) configuration under high pressure. The pressure-induced spin crossover in BiFeO(3) was investigated and confirmed by synchrotron x-ray diffraction, nuclear forward scattering, and x-ray emission methods. The insulator-metal transition at the same pressures was found by the optical absorption and dc resistivity measurements.
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12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Dudnikov V. A., Velikanov D. A., Kazak N. V., Michel C. R., Bartolome J., Arauzo A., Ovchinnikov S. G., Patrin G. S.
Заглавие : Antiferromagnetic ordering in REM cobaltite GdCoO3
Место публикации : Phys. Solid State: MAIK Nauka-Interperiodica / Springer, 2012. - Vol. 54, Is. 1. - P.79-83. - ISSN 1063-7834, DOI 10.1134/S106378341201009X
Примечания : Cited References: 16. - This study was supported by the program of the Branch of Physical Sciences of the Russian Academy of Sciences "Strong Electron Correlations," the Russian Foundation for Basic Research (project no. 09-02-00171-a), and Federal Agency for Science and Innovations (grant no. MK-5632.2010.2).
Предметные рубрики: SPIN-STATE
RCo3O3 R
Sm
Eu
Nd
Аннотация: Temperature and magnetic-field dependences of the static magnetization of polycrystalline cobaltite GdCoO3 have been measured. The magnetic properties of the GdCoO3 sample have been studied in the paramagnetic and antiferromagnetic states. The magnetic phase diagram has been constructed. The exchange field between the Gd-Gd sublattices and the anisotropy field have been estimated.
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13.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Pankrats A. I., Zharkov S. M., Zeer G. M., Gudim I. A.
Заглавие : Antiferromagnetic resonance and magnetic anisotropy in PrxY1−xFe3(BO3)4 crystals in the region of the magnetic structure transformation “easy axis – easy plane”
Место публикации : J. Alloys Compd. - 2022. - Vol. 909. - Ст.164821. - ISSN 09258388 (ISSN), DOI 10.1016/j.jallcom.2022.164821
Примечания : Cited References: 37. - The authors acknowledge the assistance of R. Mironov in some resonance measurements. The SEM and EDS investigations were conducted in the SFU Joint Scientific Center supported by the State assignment (#FSRZ-2020–0011) of the Ministry of Science and Higher Education of the Russian Federation
Аннотация: The spin dynamics, magnetic structures and magnetic anisotropy of single crystals PrxY1−xFe3(BO3)4 have been studied using antiferromagnetic resonance (AFMR) in a wide range of frequencies, magnetic fields, and temperatures. The frequency-field dependences of AFMR for the crystals with x = 0.25 and 0.45 are characteristic of antiferromagnets with the easy plane (EP) anisotropy. The crystals with x = 0.75 and 1.0 exhibit frequency-field dependences that are typical for antiferromagnets with the easy axis (EA) anisotropy. In these crystals, a significant decrease in the effective anisotropy fields of praseodymium upon the transition to the spin-flop state has been found. It is shown that this is the main reason for the large lability intervals, within which the regions of coexistence of the collinear and spin-flop states overlap. In the crystal with x = 0.67, the magnetic field applied along the trigonal axis of the crystal leads to the spin reorientation transition from the EA to the EP state. A magnetic phase diagram of the states on the plane "magnetic field - temperature" is built. In this crystal, the effective anisotropy field of praseodymium also decreases upon the transition to the field-induced EP state. Diamagnetic dilution of the praseodymium subsystem leads to the contribution of this subsystem to the total anisotropy field depending almost linearly on the praseodymium concentration.
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14.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Pankrats A., Petrakovskii G. A., Tugarinov V., Temerov V.
Заглавие : Antiferromagnetic resonance and phase diagram of HoFe3(BO3)4
Коллективы : Российская академия наук, Физико-технический институт им. А.Ф. Иоффе РАН, "Spin Waves", International Symposium
Место публикации : International Symposium "Spin waves - 2009": Saint Petersburg, Russia, June 7-12, 2009 : Simposium program. Abstracts. - 2009. - С. 40
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15.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kazak N. V., Belskaya N. A., Moshkina E. M., Bezmaternykh L. N., Vasiliev A. D., Sofronova S. N., Eremina R. M., Eremin E. V., Muftakhutdinov A. R., Cherosov M. A., Ovchinnikov S. G.
Заглавие : Antiferromagnetism of the cation-ordered warwickite system Mn2-xMgxBO4 (x=0.5, 0.6 and 0.7)
Коллективы : Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR) [20-02-00559]; Government of Krasnoyarsk Territory; Krasnoyarsk Regional Fund of Science to the research project [18-42243007]
Место публикации : J. Magn. Magn. Mater. - 2020. - Vol. 507. - Ст.166820. - ISSN 0304-8853, DOI 10.1016/j.jmmm.2020.166820. - ISSN 1873-4766(eISSN)
Примечания : Cited References: 39. - The reported study was funded by the Russian Foundation for Basic Research (no. 20-02-00559), Government of Krasnoyarsk Territory, Krasnoyarsk Regional Fund of Science to the research project. 18-42243007.
Предметные рубрики: SPIN-GLASS BEHAVIOR
CRYSTAL-STRUCTURES
SINGLE-CRYSTALS
INSIGHTS
MGFEBO4
Аннотация: X-ray diffraction, heat capacity and magnetic measurements are performed on single crystals of Mn2-xMgxBO4 (x = 0.5, 0.6 and 0.7) with the warwickite structure. The monoclinic symmetry is found for all samples with the space group P21/n. The M1 site is occupied by trivalent Mn ions while the M2 site is occupied by a mixture of divalent Mg and Mn ions. Regular cation and charge distributions are observed, which is unusual for heterometallic warwickites. The local octahedral distortions of M1O6 show the monotonic dependence on the Mg content and are in accordance with the Jahn-Teller distortion. All samples are found to undergo long-range antiferromagnetic ordering with rather low transition temperatures of TN = 16, 14 and 13 K for x = 0.5, 0.6, and 0.7, respectively. The ordering of local octahedral distortions, caused by the strong electron-phonon interaction of the trivalent Mn ions, is proposed to stabilise the cationic ordering and, as a result, the long-range magnetic ordering in the material.
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16.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Martynov S. N.
Заглавие : Antisymmetric Exchange in the CuB2O4 A Subsystem
Место публикации : JETP Letters. - 2009. - Vol. 90, Is. 1. - P.55-58. - ISSN 0021-3640, DOI 10.1134/S0021364009130116
Примечания : Cited References: 31
Предметные рубрики: TRANSVERSE MAGNETIC-FIELD
FLUCTUATION-INDUCED PHASE
COPPER METABORATE
ANTIFERROMAGNETIC CHAINS
SOLITON LATTICE
INDUCED GAP
SPIN-WAVES
BA2CUGE2O7
CSCUCL3
MNSI
Аннотация: The space distribution of the components of the microscopic Hamiltonian of the antisymmetric Dzyaloshinskii-Moriya exchange with respect to the exchange bond pairs of the A subsystem of Cu2+ ions in the crystallographic 4b positions of CuB2O4 has been obtained using symmetry analysis. The possibility of the coexistence of two different types of the exchange spatial distribution is demonstrated. The component of the anti-symmetric exchange vector D parallel to the tetragonal axis has a weakly ferromagnetic distribution for all of the directions of the bonds between the nearest magnetic neighbors. Each exchange bond has an additional component of the antisymmetric exchange parallel to the bond projection on the tetragonal plane. The spatial distribution of these components is helicoidal with the modulation vector in the tetragonal crystal plane.
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17.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Valkov V. V., Valkova T. A.
Заглавие : Application of indefinite metric for transition to bose description of Su(3) hamiltonians - excitation spectrum of spin nematics
Место публикации : Zhurnal Eksperimentalnoi Teor. Fiz. - 1991. - Vol. 99, Is. 6. - P.1881-1897. - ISSN 0044-4510
Примечания : Cited References: 37
Предметные рубрики: BIQUADRATIC EXCHANGE
PHASE-TRANSITIONS
DIAGRAM TECHNIQUE
MAGNETISM
FIELD
STATE
Аннотация: A procedure is developed for a correct transition to the Bose representation for quantum SU(3) Hamiltonians. The analysis is carried out for a spin nematic by applying the indefinite metric formalism and pseudo-Hubbard operators. An important aspect of the theory is that the finiteness of the number of physical states is taken into account. This is attained by introducing and consistently taking into account the metric operator for which purpose a simple expression in terms of Bose operators is suggested. It is shown that in this approach the quantum Bose analog of the Hamiltonian is an Hermitian operator. This circumstance removes a number of principle contradictions which appeared previously on application of the Bose analog of the Hamiltonian derived by virtually identifying the Hubbard and pseudo-Hubbard operators and ignoring the finiteness of the number of physical states. The integral equations defining the chief characteristics of the system are obtained and solved analytically for the spin-nematic state of a magnet with S = 1 and by taking into account anharmonic effects. This permits one to write down in nonlinear theory explicit expressions for the two branches of the quantum excitation spectrum. The character of the renormalization of the spectrum parameters due to the presence of zero-point quantum oscillations is studied. The renormalization of the critical field on transition of the system from the spin nematic state is calculated analytically.
WOS
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18.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ovchinnikov S. G.
Заглавие : Application of synchrotron radiation to the study of magnetic materials
Место публикации : Uspekhi Fiz. Nauk: MEZHDUNARODNAYA KNIGA, 1999. - Vol. 169, Is. 8. - P.869-887. - ISSN 0042-1294
Примечания : Cited References: 93
Предметные рубрики: X-RAY-SCATTERING
RESONANCE EXCHANGE SCATTERING
RARE-EARTH-METALS
CIRCULAR-DICHROISM
VALENCE STATES
CO/PD(111) MULTILAYERS
ABSORPTION-SPECTRA
PHASE-TRANSITIONS
SPIN POLARIZATION
EDGE STRUCTURE
Аннотация: The recent results of the studies of magnetic materials using synchrotron irradiation are reviewed. The influence of magnetic effects on X-ray scattering is studied for linearly and circularly polarized photons, and effects of magnetic circular dichroism on the spectra of X-ray absorption and photoelectron emission are discussed. It is shown that X-ray magnetooptics techniques provide fine details of crystal and magnetic structures and also make it possible to separate the spin and orbital contributions to the total moment; to obtain element- and position-sensitive information on the magnetic properties of the material; to visualize domains and domain walls; and to probe magnetization reversal dynamics. A comparison of magnetic neutron and X-ray methods is given.
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19.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Lundin A. A., Zobov V. E.
Заглавие : Asymptotic similarity of time correlation functions and shape of the 13C and 29Si NMR spectra in diamond and silicon
Коллективы : Institute of Chemical Physics of the Russian Academy of Science [0082-2018-0005, TSITIS AAAA-A18-118020690203]
Место публикации : J. Exp. Theor. Phys. - 2018. - Vol. 127, Is. 2. - P.305-315. - ISSN 1063-7761, DOI 10.1134/S1063776118080216. - ISSN 1090-6509(eISSN)
Примечания : Cited References: 47. - We thank V.A. Atsarkin, V.V. Demidov, F.S. Dzheparov, and E. B. Feldman for the discussion of our results. This work was supported by a subsidy allocated by the Institute of Chemical Physics of the Russian Academy of Science for the State assignment, theme 0082-2018-0005, code TSITIS AAAA-A18-118020690203.
Предметные рубрики: SPIN SYSTEMS
LINE-SHAPES
RELAXATION
SOLIDS
PARAMAGNETS
RESONANCE
Аннотация: Based on the proposed theory, we have investigated the shape of the NMR absorption spectra for 13C and 29Si nuclei in diamond and silicon crystals attributable to the internuclear dipole–dipole interaction. In accordance with the available experimental data, we have considered both crystals with a 100% content of magnetoactive isotopes and crystals with a comparatively low dilution by nonmagnetic nuclei. The time correlation functions (the first of which is the Fourier transform of the NMR spectrum) arising in an infinite chain of coupled differential equations are shown to be mutually similar with a slight time delay. The proposed theory allows the spectrum to be calculated analytically. The results obtained agree satisfactorily with the experimental ones. It is noted that the mutual similarity of the time correlation functions is probably a corollary of the development of dynamical chaos in the system.
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20.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Avramov P., Sakai S., Entani S., Matsumoto Y., Naramoto H., Ohtomo M.
Заглавие : Atomic and Electronic Structure of Graphene- and Multigraphene-based 2D Extended Complex Nanocom­posites
Коллективы : International Workshop on Spin Currents
Место публикации : 5th International Workshop on Spin Currents. - 2011. - С. 2-14
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