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

Формат представления найденных документов:
полный	информационный	краткий

Отсортировать найденные документы по:
автору	заглавию	году издания	типу документа

Поисковый запрос: (<.>K=Vectors<.>)

Общее количество найденных документов : 12
Показаны документы с 1 по 10

1-10 11-12

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Martynov S. N.
Заглавие : The incommensurate magnetic structure of a tetragonal antiferromagnet with antisymmetric exchange
Место публикации : J. Exp. Theor. Phys. - 2009. - Vol. 109, Is. 6. - P.979-988. - ISSN 1063-7761, DOI 10.1134/S1063776109120097
Примечания : Cited References: 34
Предметные рубрики: FLUCTUATION-INDUCED PHASE
FIELD-INDUCED GAP
COPPER METABORATE
WEAK FERROMAGNETISM
SOLITON LATTICE
SPIN-WAVES
CUB2O4
BA2CUGE2O7
CSCUCL3
CHAINS
Ключевые слова (''Своб.индексиров.''): anti-symmetric--antiferromagnetic sublattices--antiferromagnets--antisymmetric exchange--exchange bonds--ferromagnetic component--ferromagnetic moments--ginzburg-landau functional--incommensurate magnetic structures--mean field approximation--modulation vectors--polarization planes--polarization vectors--symmetry groups--antiferromagnetic materials--antiferromagnetism--crystal orientation--crystal symmetry--ferromagnetic materials--ferromagnetism--magnetic devices--magnetic structure--modulation--polarization--vector spaces--vectors--crystallography
Аннотация: Analysis of the incommensurate magnetic structure that emerges for two coexisting types of the antisymmetric Dzyaloshinski-Moriya exchange interaction (the weakly ferromagnetic component of vector D along the tetragonal axis and the helicoidal component distributed in the tetragonal plane) is carried out for the first time for a tetragonal antiferromagnet. The helicoidal component for each pair of interacting spins has a 2D distribution; its direction in the tetragonal plane depends on the direction of the exchange bond in each pair. The Lifshits invariant of the Ginzburg-Landau functional is obtained, which is responsible for the formation of an incommensurate magnetic structure for such a distribution. It is shown in the mean field approximation that the incommensurate magnetic structure that forms in this case is a nonlinear double helicoid with a modulation vector lying in the tetragonal plane and with a varying angle between the polarization planes of quasi-antiferromagnetic sublattices. The ground state of the magnet is degenerate in the orientation of the modulation vector in the tetragonal plane. The rate of variation in the orientations of moments in the polarization planes passing through the tetragonal axis is controlled by the angle between the directions of the moments and the tetragonal axis. The local weakly ferromagnetic moment remaining in the polarization plane varies in magnitude and sign. The relation between the orientations of the modulation and polarization vectors is derived for the cases of simple and inversion tetragonal axes in the space symmetry group of the crystal.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Fischer P., Pomjakushin V., Sheptyakov D., Keller L., Janoschek M., Roessli B., Schefer J., Petrakovskii G. A., Bezmaternykh L. N., Temerov V. L., Velikanov D. A.
Заглавие : Simultaneous antiferromagnetic Fe3+ and Nd3+ ordering in NdFe3((BO3)-B-11)(4)
Разночтения заглавия :авие SCOPUS: Simultaneous antiferromagnetic Fe3+ and Nd3+ ordering in NdFe3(11BO3)4
Место публикации : J. Phys.: Condens. Matter: IOP PUBLISHING LTD, 2006. - Vol. 18, Is. 34. - P.7975-7989. - ISSN 0953-8984, DOI 10.1088/0953-8984/18/34/010
Примечания : Cited References: 20
Предметные рубрики: PHASE-TRANSITION
DIFFRACTION
CRYSTALS
GDFE3(BO3)(4)
SINQ
Ключевые слова (''Своб.индексиров.''): iron compounds--magnetic moments--magnetization--neodymium compounds--neutron diffraction--vectors--crystal-field effects--free ion moment--specific heat measurements--symmetry analysis--antiferromagnetic materials
Аннотация: By means of magnetic susceptibility and specific heat measurements, x-ray and unpolarized neutron diffraction investigations on powder and single-crystal samples, simultaneous long-range antiferromagnetic Fe and Nd ordering in NdFe3((BO3)-B-11)(4) with R32 chemical structure has been found at temperatures below T-N = 30.5(5) K down to 1.6 K. At temperatures down to 19 K the propagation vector is k(hex) = [0, 0, 3/2] and becomes slightly incommensurate at lower temperatures. Combined with symmetry analysis, best powder neutron profile fits are obtained with magnetic spiral configurations with the magnetic moments oriented parallel to the hexagonal basal plane according to the irreducible representations tau(3) in the commensurate case. This is in agreement with the easy directions of magnetization perpendicular to the c-axis as determined by magnetic susceptibility measurements. At 1.6 K the magnetic Fe moment amounts to 4.9 mu(B) B close to the free ion moment of Fe3+. The magnetic Nd3+ moment saturates presumably due to crystal-field effects at 2.7 mu(B).
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Vtyurin A. N., Isaenko L. I., Krylova S. N., Yelisseyev A., Shebanin A. P., Turchin P. P., Zamkova N. G., Zinenko V. I.
Заглавие : Raman spectra and elastic properties of KPb2Cl5 crystals
Место публикации : 11th International Conference on Phonon Scattering in Condensed Matter (PHONONS 2004) (JUL 25-30, 2004, St Petersburg, RUSSIA): WILEY-V C H VERLAG GMBH, 2004. - P3142-3145. - ISBN 3-527-40588-7, DOI 10.1002/pssc.200405401
Примечания : Cited References: 10
Предметные рубрики: LATTICE-DYNAMICS
Ключевые слова (''Своб.индексиров.''): computer simulation--crystal structure--eigenvalues and eigenfunctions--halogen compounds--nonlinear optics--phonons--potassium compounds--vectors--elastic constants--heavy cations--ionic electron envelopes--ionic interactions--raman scattering
Аннотация: Raman scattering spectra and elastic constants of KPb2Cl5 crystals have been studied. The results obtained are interpreted in terms of the ab initio lattice dynamics model taking into account multipole moments of ionic electron envelopes. The experimental results have been found to be in good agreement with numerical simulation; the narrow phonon spectra are shown to be due to a considerable contribution of heavy cations into the eigenvectors of the higher frequency lattice modes.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Bolsunovskaya O. A., Petrakovskii G. A., Popov M.
Заглавие : Interaction of a two spin subsistems with the different wave vectors
Коллективы : Moscow International Symposium on Magnetism, Московский государственный университет им. М.В. Ломоносова, Российский фонд фундаментальных исследований
Место публикации : Moscow Int. Symp. on Magnet. (MISM-2008): June 20-25, 2008, Moscow : book of abstract. - 2008. - Ст.24PO-6-21. - p.609-610
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Martynov S. N.
Заглавие : Phase diagram of the helical structure of a two-subsystem frustrated antiferromagnet
Место публикации : J. Exp. Theor. Phys.: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2009. - Vol. 108, Is. 1. - P72-82. - ISSN 1063-7761, DOI 10.1134/S1063776109010105
Примечания : Cited References: 25
Предметные рубрики: GROUND SPIN-STATE
PYROCHLORE ANTIFERROMAGNET
TRIANGULAR-LATTICE
CLASSICAL-THEORY
MODEL
TRANSITION
Ключевые слова (''Своб.индексиров.''): antiferromagnetic materials--antiferromagnetism--free energy--magnetic devices--magnetic fields--magnetic structure--phase diagrams--vectors--antiferromagnet--antiferromagnetic--antiferromagnetic sublattices--comparative analysis--critical fields--external fields--field boundaries--first derivatives--first-order transitions--helical orderings--helical phase--helical structures--higher temperatures--incommensurate magnetic structures--isotropic exchanges--magnetic subsystems--magnetization jumps--mean-field approximations--minimum free energies--numerical minimizations--spatial displacements--temperature dependences--thermodynamic potentials--variational equations--wave vectors--phase transitions
Аннотация: The expansion of the thermodynamic potential for the two-subsystem antiferromagnet with frustrated intersubsystem isotropic exchange is obtained. It is demonstrated that this expansion contains the first derivatives with respect to the antiferromagnetic vectors of the subsystems, i.e., the Lifshitz invariant. The equation for the temperature-field boundary of the helical phase for the two-subsystem frustrated antiferromagnet is derived by linearizing the variational equations for the minimum free energy within the mean-field approximation. Relationships are obtained for the critical field at T = 0, the angle of canting of moments of the antiferromagnetic sublattices, and the temperature of spontaneous appearance of helical ordering in the absence of an external field. It is revealed that there is a second higher temperature of formation of the helical magnetic structure induced by the magnetic field with the wave vector of the helix nonmonotonically depending on the external field. The phase boundary of the helical phase and the temperature dependence of the orientation of moments of the magnetic subsystem with weak exchange interaction are determined using numerical minimization of the free energy. It is shown that the transition to the commensurate phase is a first-order transition with a small magnetization jump. A comparative analysis of models with different spatial displacements of ions in the subsystems along the direction of the vector of the helical structure is performed. A criterion is proposed for the choice of the direction of the vector of the incommensurate magnetic structure.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Davydov V. Yu., Klochikhin A. A., Smirnov A. N., Strashkova I. Y., Krylov A. S., Lu H., Schaff W. J., Lee H. M., Hong Y. L., Gwo S.
Заглавие : Selective excitation of E-1(LO) and A(1)(LO) phonons with large wave vectors in the Raman spectra of hexagonal InN
Коллективы : RFBR [09-02-01280]; NSC-RFBR [08-02-92003-HHC]
Разночтения заглавия :авие SCOPUS: Selective excitation of E1 (LO) and A1 (LO) phonons with large wave vectors in the Raman spectra of hexagonal InN
Место публикации : Phys. Rev. B. - 2009. - Vol. 80, Is. 8. - Ст.81204. - ISSN 1098-0121, DOI 10.1103/PhysRevB.80.081204
Примечания : Cited References: 15. - We are thankful to B. N. Mavrin and A. N. Vtyurin for the arrangement NIR measurements and S. A. Permogorov for the critical reading of the manuscript. This work was supported by RFBR (Grant No. 09-02-01280), NSC-RFBR (Grant No. 08-02-92003-HHC), and the Program of RAS "New materials and structures."
Предметные рубрики: SCATTERING
RESONANCE
Ключевые слова (''Своб.индексиров.''): iii-v semiconductors--indium compounds--phonon dispersion relations--raman spectra--wide band gap semiconductors
Аннотация: It is shown that dispersions of E-1(LO) and A(1)(LO) modes of InN can be restored in a wide interval of wave vectors by studying impurity-induced first-order Raman scattering as a function of exciting light energy. It is also shown that due to the resonance character of scattering the observed phonon energies correspond to the wave vectors strictly defined by exciting photon energies. The frequencies of E-1(LO) and A(1)(LO) phonons at the Gamma point obtained by extrapolation to zero wave vectors were found to be 604 and 592 cm(-1), respectively.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Arkhipkin V. G., Timofeev I. V.
Заглавие : Spatial evolution of short laser pulses under coherent population trapping
Место публикации : Physical Review A - Atomic, Molecular, and Optical Physics. - 2001. - Vol. 64, Is. 5. - P.538111-538118. - ISSN 1050-2947
Примечания : Cited References: 30
Ключевые слова (''Своб.индексиров.''): computer simulation--ground state--light propagation--mathematical models--photons--vectors--wave equations--adiabatic population transfer (apt)--laser pulses
Аннотация: Spatial and temporal evolution of two powerful short laser pulses having different wavelengths and interacting with a dense three-level optical medium under coherent population trapping was studied. The duration of the probe pulse and the coupling pulse were assumed to be shorter than any of the relevant atomic relaxation times. Propagation dynamics was found to be strongly dependent on the ratio of the transition oscillator strengths. It was shown that the envelopes of the pulses slightly changed throughout the medium length in the initial stage of propagation.
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Sandalov I. S., Padyukov, Leonid
Заглавие : Genetic vectors as a tool in association studies: Definitions and application for study of rheumatoid arthritis
Коллективы : Swedish Research Council, Vinnova (COMBINE Grant); Innovative Medicines Initiative Joint Undertaking [115142-2 BTCURE]
Место публикации : Int. J. Genomics. - 2015. - Ст.256818. - ISSN 2314, DOI 10.1155/2015/256818. - ISSN 23144378(eISSN)
Примечания : Cited References:10. - This study was supported by the Swedish Research Council, Vinnova (COMBINE Grant), and Innovative Medicines Initiative Joint Undertaking, 115142-2 BTCURE. The authors would like to thank Janet Ahlberg for help with English editing of the paper.
Предметные рубрики: FAMILIES
Аннотация: To identify putative relations between different genetic factors in the human genome in the development of common complex disease, we mapped the genetic data to an ensemble of spin chains and analysed the data as a quantum system. Each SNP is considered as a spin with three states corresponding to possible genotypes. The combined genotype represents a multispin state, described by the product of individual-spin states. Each person is characterized by a single genetic vector (GV) and individuals with identical GVs comprise the GV group. This consolidation of genotypes into GVs provides integration of multiple genetic variants for a single statistical test and excludes ambiguity of biological interpretation known for allele and haplotype associations. We analyzed two independent cohorts, with 2633 rheumatoid arthritis cases and 2108 healthy controls, and data for 6 SNPs from the HTR2A locus plus shared epitope allele. We found that GVs based on selected markers are highly informative and overlap for 98.3% of the healthy population between two cohorts. Interestingly, some of the GV groups contain either only controls or only cases, thus demonstrating extreme susceptibility or protection features. By using this new approach we confirmed previously detected univariate associations and demonstrated the most efficient selection of SNPs for combined analyses for functional studies.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kolovsky A. R., Mantica G.
Заглавие : Cyclotron-Bloch dynamics of a quantum particle in a two-dimensional lattice
Место публикации : Physical Review E - Statistical, Nonlinear, and Soft Matter Physics. - 2011. - Vol. 83, Is. 4. - Ст.041123. - ISSN 1539-3755, DOI 10.1103/PhysRevE.83.041123
Ключевые слова (''Своб.индексиров.''): critical value--directed transport--drift velocities--electric and magnetic fields--electric field magnitude--electric field vectors--free space--initial conditions--lattice plane--quantum dynamics--quantum particles--quantum wave packets--two dimensional square lattice--two-dimensional lattices--electric fields--magnetic fields--quantum theory--vector spaces--two dimensional
Аннотация: This paper studies the quantum dynamics of a charged particle in a two-dimensional square lattice, under the influence of electric and magnetic fields, the former being aligned with one of the lattice axes and the latter perpendicular to the lattice plane. While in free space these dynamics consist of uniform motions in the direction orthogonal to the electric field vector, we find that, in a lattice, this directed drift takes place only for specific initial conditions and for electric field magnitudes smaller than a critical value. Otherwise, the quantum wave packet spreads ballistically in both directions orthogonal to the electric field. We quantify this ballistic spreading and identify the subspace of initial conditions ensuring directed transport with the drift velocity. We also describe the effect of disorder in the system. В© 2011 American Physical Society.
Scopus,
Читать в сети ИФ
Найти похожие

10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Erkaev N. V., Shaidurov V. A., Semenov V. S., Langmayr D., Biernat H. K.
Заглавие : Peculiarities of Alfven wave propagation along a nonuniform magnetic flux tube
Место публикации : Phys. Plasmas: AMER INST PHYSICS, 2005. - Vol. 12, Is. 1. - Ст.12905. - ISSN 1070-664X, DOI 10.1063/1.1833392
Примечания : Cited References: 18
Предметные рубрики: HYDROMAGNETIC-WAVES
TRANSFER EVENTS
FIELD
SLOW
Ключевые слова (''Своб.индексиров.''): algebra--approximation theory--boundary conditions--electric conductivity--electric field effects--integral equations--magnetic flux--magnetohydrodynamics--perturbation techniques--polarization--vectors--velocity measurement--alfven wave propagation--axial symmetry--magnetic flux tubes--magnetosonic pulses--wave propagation
Аннотация: Within the framework of the assumption of large azimuthal wave numbers, the equations for Alfven and slow magnetosonic waves are obtained using frozen-in material coordinates. These equations are specified for the case of a nonuniform magnetic field with axial symmetry. Assuming a meridional polarization of the magnetic field and velocity perturbations, the effects of Alfven wave propagation are analyzed which are related to geometric characteristics of a nonuniform magnetic field: (a) A finite curvature radius of the magnetic field lines and (b) convergence of magnetic field lines. The interaction between the Alfven and magnetosonic waves is found to be strongly dependent on the curvature radius of the magnetic tube and the local plasma beta parameter. The electric field amplitude and the length scale of a wave front are found to increase very strongly in the course of the Alfven wave propagation along a converging magnetic flux tube. Also studied is a temporal decrease of the wave perturbations which is caused by dissipation at the conducting boundary. (C) 2005 American Institute of Physics.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие