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=Antiferromagnet<.>)

Общее количество найденных документов : 75
Показаны документы с 1 по 20

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.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aplesnin S. S.
Заглавие : A study of anisotropic Heisenberg antiferromagnet with S=1/2 on a square lattice by Monte-Carlo method
Место публикации : Phys. Status Solidi B. - 1998. - Vol. 207, Is. 2. - P.491-498. - ISSN 0370-1972, DOI 10.1002/(SICI)1521-3951(199806)207:2491::AID-PSSB4913.0.CO;2-G
Примечания : Cited References: 24
Предметные рубрики: EU2CUO4
LA2CUO4
ORDER
MODEL
STATE
Аннотация: The two-dimensional (2D) Heisenberg model (J 0) with anisotropic exchange Delta = 1-J(X)/J(Z) greater than or equal to 0 and with S = 1/2 is studied by the quantum Monte-Carlo method. Energy, susceptibility, specific heat, spin-spin correlation functions, and correlation radius are calculated. The dependence of the Neel temperature T(N)/J = 2/ln(11/Delta) on the exchange anisotropy is determined. The static magnetic factor is very slowly decreased for T/J 0.4. It is assumed to realize topological excitations in the range of these temperatures. The correlation radius of the isotropic Heisenberg model is fitted by the dependence 1/xi = 2.05T(1.0(6))/exp (1.0(4)/T).The temperature behavior of the static structural magnetic factor in La(2)CuO(4) and Er(2)CuO(4) for T T(N) is in agreement with the MC calculations.
WOS
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Popov E. A., Beznosikov B. V.
Заглавие : Absorption of light by exchange-coupled ions in a 2D antiferromagnet
Место публикации : Phys. Solid State. - 2003. - Vol. 45, Is. 8. - P.1475-1478. - ISSN 1063-7834, DOI 10.1134/1.1602882
Примечания : Cited References: 9
Предметные рубрики: OPTICAL-ABSORPTION
RB2MNCL4
Аннотация: The optical absorption spectra of Rb2MnxCd1-xCl4 crystals are experimentally studied in the vicinity of a magnon sideband of the exciton band at a manganese content x ranging from 1.0 to 0.4. Additional absorption bands are observed with an increase in the magnetic structural disorder upon replacement of manganese ions by cadmium ions. An analysis of the evolution of the additional absorption bands in a magnetic field during the spin-flop phase transition and the change in the intensity with variations in the manganese content x demonstrates that these bands are associated with the excitation of the exchange-coupled pairs of manganese ions located in different environments in a plane square lattice. The phase boundary between the antiferromagnetic and spin-flop phases is constructed using the results of optical measurements. The manganese content corresponding to the magnetic percolation point is evaluated. (C) 2003 MAIK "Nauka/Interperiodica".
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Petrakovskii G. A., Ryabinkina L. I., Abramova G. M., Velikanov D. A., Bovina A. F.
Заглавие : Antiferromagnet-ferromagnet transition in alpha-MnxS manganese sulfides
Разночтения заглавия :авие SCOPUS: Antiferromagnet-ferromagnet transition in α-MnxS manganese sulfides; авие SCOPUS: Antiferromagnet-ferromagnet transition in ?-MnxS manganese sulfides
Место публикации : Phys. Solid State: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2001. - Vol. 43, Is. 3. - P493-495. - ISSN 1063-7834, DOI 10.1134/1.1356126; Phys. Solid State. - 2001. - Vol. 43, Is. 3. - P493-495. - Вариант Sopus
Примечания : Cited References: 7
Аннотация: Off-stoichiometric manganese monosulfides alpha -MnxS (1 less than or equal to x less than or equal to 1.25) are synthesized, and their crystal structure and magnetic properties are studied in the 4.2- to 300-K range. The compounds have a NaCl fcc lattice. Increasing the manganese ion concentration x in the antiferromagnetic semiconductors alpha -MnxS is found to result in concentration- (x(c) similar to 1.05) and temperature-driven (T-c similar to 50 K) magnetic transitions from the antiferromagnetic to ferromagnetic state, with the cubic structure remaining unchanged. (C) 2001 MAIK "Nauka/Interperiodica".
WOS,
Scopus,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kobets M.I., Dergachev K.G., Khatsko E.N., Gnatchenko S.L., Bezmaternykh L. N., Temerov V. L.
Заглавие : Antiferromagnetic resonance in ferroborate NdFe3(BO3)(4)
Место публикации : Physica B. - 2011. - Vol. 406, Is. 18. - P.3430-3435. - SEP 15. - ISSN 0921-4526, DOI 10.1016/j.physb.2011.06.014. - ISSN 1873-2135
Примечания : Cited Reference Count: 19
Предметные рубрики: Physics, Condensed Matter
Ключевые слова (''Своб.индексиров.''): antiferromagnet--resonance--multiferroics--commensurate-incommensurate phase
Аннотация: The AFMR spectra of the NdFe3(BO3)(4) crystal are measured in a wide range of frequencies and temperatures. It is found that by the type of its magnetic anisotropy the compound is an easy-plane antiferromagnet with a weak anisotropy in the basal plane. The effective magnetic parameters are determined: anisotropy fields H-a1 = 1.14 kOe and H-a2 = 60 kOe and magnetic excitation gaps Delta v(1) = 101.9 GHz and Delta v(2) = 23.8 GHz. It is shown that commensurate-incommensurate phase transition causes a shift in resonance field and a considerable change in absorption line width. At temperatures below 4.2 K nonlinear regimes of AFMR excitation at low microwave power levels are observed. (C) 2009 Elsevier B.V. All rights reserved.
WOS
Найти похожие

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.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Val'kov V. V., Dzebisashvili D. M., Barabanov A. F.
Заглавие : Basis states and collective excitations of nonlocal three-spin polarons over the singlet phase of the CuO2 plane
Место публикации : JETP Letters. - 2012. - Vol. 95, Is. 4. - P.206-212. - ISSN 0021-3640, DOI 10.1134/S0021364012040091
Примечания : Cited References: 15. - This work was supported by the Presidium of the Russian Academy of Sciences (program "Quantum Physics of Mesoscopic and Disordered Systems"), the Russian Foundation for Basic Research (project nos. 10-02-00251 and 11-02-98007-r-sibir'), and the Ministry of Education and Science of the Russian Federation (federal program "Human Capital for Science and Education in Innovative Russia" for 2009-2013).
Предметные рубрики: HEISENBERG-ANTIFERROMAGNET
SQUARE LATTICE
SPIN-POLARON
MODEL
Аннотация: An orthonormalized basis describing the single-hole states of the CuO2 plane has been constructed exactly taking into account the p-d exchange coupling between the spins of a hole and the two nearest copper ions. The introduced basis makes it possible to include the effects caused by the dependence of the Heisenberg interaction between the nearest copper ions on the occupation of the intermediate oxygen ion by the hole in the calculation of the spectrum of the collective excitations of nonlocal three-spin polarons. The inclusion of this correlation, as well as the nonlocality of the p-d exchange coupling, is the main difference of the developed approach to the description of the energy structure from the calculations with the use of the Zhang-Rice singlet.
Смотреть статью,
Scopus,
WoS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Boldyrev K. N., Stanislavchuk T. N., Sirenko A. A., Kamenskyi D., Bezmaternykh L. N., Popova M. N.
Заглавие : Bifurcations of coupled electron-phonon modes in an antiferromagnet subjected to a magnetic field
Место публикации : Phys. Rev. Lett.: American Physical Society, 2017. - Vol. 118, Is. 16. - Ст.167203. - ISSN 00319007 (ISSN), DOI 10.1103/PhysRevLett.118.167203
Примечания : Cited References: 26. - This research was supported by the Russian Scientific Foundation under Grant No. 14-12-01033, the President of Russian Federation (MK-3577.2017.2, K. N. B.), and the U.S. Department of Energy under Grant No. DE-FG02-07ER46382 (experiments at U4-IR beam line NSLS-BNL, T. N. S. and A. A. S.). The National Synchrotron Light Source is operated as a user facility for the U.S. Department of Energy under Contract No. DE-AC02-98CH10886. Part of this work was supported by EMFL (Contract No. 26211). M. N. P. thanks B. Z. Malkin and A. V. Popov for helpful discussions.
Ключевые слова (''Своб.индексиров.''): antiferromagnetic materials--bifurcation (mathematics)--electron-phonon interactions--electrons--magnetic fields--magnetism--temperature--antiferromagnetic crystals--bifurcation points--electron phonon couplings--electronic excitation--external magnetic field--field independents--low temperatures--reflection spectra--phonons
Аннотация: We report on a new effect caused by the electron-phonon coupling in a stoichiometric rare-earth antiferromagnetic crystal subjected to an external magnetic field, namely, the appearance of a nonzero gap in the spectrum of electronic excitations in an arbitrarily small field. The effect was registered in the low-temperature far-infrared (terahertz) reflection spectra of an easy-axis antiferromagnet PrFe3(BO3)4 in magnetic fields Bext-c. Both paramagnetic and magnetically ordered phases (including a spin-flop one) were studied in magnetic fields up to 30 T, and two bifurcation points were observed. We show that the field behavior of the coupled modes can be successfully explained and modeled on the basis of the equation derived in the framework of the theory of coupled electron-phonon modes, with the same field-independent electron-phonon interaction constant |W|=14.8 cm-1. © 2017 American Physical Society.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Krinitsyn A., Nikolaev S., Ovchinnikov S. G.
Заглавие : Cluster size and shape effect on the electronic structure of the Hubbard model within the norm-conserving cluster perturbation theory
Коллективы : Siberian Federal University [F-11]; Presidium of RAS Program [20.7]; [NSh-1044.2012.2]; [MK-1168.2012.2]
Место публикации : J. Supercond. Nov. Magn.: Springer, 2014. - Vol. 27, Is. 4. - P.955-963. - ISSN 1557-1939, DOI 10.1007/s10948-013-2418-7. - ISSN 1557-1947
Примечания : Cited References: 59. - This work was supported by Grants NSh-1044.2012.2 and MK-1168.2012.2, Siberian Federal University: Grant F-11, and the Presidium of RAS Program 20.7.
Предметные рубрики: NARROW ENERGY-BANDS
CUPRATE SUPERCONDUCTORS
PHOTOEMISSION SPECTRA
PSEUDOGAP
ANTIFERROMAGNET
EXCITATIONS
EVOLUTION
SYSTEMS
PHASE
STATE
Ключевые слова (''Своб.индексиров.''): cluster perturbation theory--hubbard model--strong correlations--density of states--fermi surface
Аннотация: Within a new norm-conserving approach to the cluster perturbation theory (CPT) for the 2d Hubbard model we study the effect of the cluster size and shape on the electronic structure. We have compared two type of clusters, 4-cluster (2x2) and 5-cluster (cruciform of 5 atoms). With 4-cluster we can treat exactly the first and second neighbours correlations, C (1) and C (2). With 5-cluster the third neighbour correlations C (3) are also treated exactly. The band structure in the CPT with 4- and 5-clusters differs remarkably. The quasiparticle spectral weight map for 5-clusters is very similar to the Quantum Monte Carlo (QMC) and the variational CPT data. With increasing doping, small hole Fermi surface transforms into conventional Fermi-liquid type large Fermi surface through Lifshitz quantum phase transitions.
Смотреть статью,
Scopus,
WoS,
Читать в сети ИФ
Найти похожие

10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aplesnin S. S.
Заглавие : Dimerization of antiferromagnetic chain with 4-spin interaction
Место публикации : Fiz. Tverd. Tela: MEZHDUNARODNAYA KNIGA, 1996. - Vol. 38, Is. 6. - P1868-1877. - ISSN 0367-3294
Примечания : Cited References: 30
Предметные рубрики: SPIN-1/2 HEISENBERG-ANTIFERROMAGNET
COMPETING INTERACTIONS
MONTE-CARLO
THERMODYNAMIC PROPERTIES
SYSTEMS
CUGEO3
TEMPERATURE
NEUTRON
STATE
MODEL
WOS
Найти похожие

11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Val'kov V. V., Korovushkin M. M., Barabanov A. F.
Заглавие : Effective Interactions and the Nature of Cooper Instability of Spin Polarons in the 2D Kondo Lattice
Коллективы :
Разночтения заглавия :авие SCOPUS: Effective interactions and the nature of Cooper instability of spin polarons in the 2D Kondo lattice
Место публикации : JETP Letters. - 2008. - Vol. 88, Is. 6. - P.370-374. - ISSN 0021-3640, DOI 10.1134/S0021364008180069
Примечания : Cited References: 9. - This work was supported by the Presidium of the Russian Academy of Sciences (program "Quantum Microphysics"), the Russian Foundation for Basic Research (project no. 06-02-16100), and the Siberian Branch, Russian Academy of Sciences (integration project no. 3.4). The work of M. M. Korovushkin was supported by the Krasnoyarsk Regional Science Foundation (project no. 18G).
Предметные рубрики: SUPERCONDUCTIVITY
ANTIFERROMAGNET
MODEL
Аннотация: It has been shown that two- and three-center interactions arise in the strong-coupling regime for the 2D Kondo lattice; these interactions both induce and suppress the Cooper instability. It is important that, in contrast to the t-J* model, the three- center interactions promote the Cooper pairing and ensure the appearance of the superconducting phase with a high critical temperature T(c). The calculated concentration dependences of T(c) agree well with the experimental data for the cuprate superconductors.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Troyanchuk I. O., Bushinsky M. V., Tereshko N. V., Lanovsky R. A., Sikolenko V. V., Ritter C., Orlov Yu. S., Ovchinnikov S. G.
Заглавие : Ferromagnet-antiferromagnet transition in layered perovskites of Sr3YCo4O10.5 type
Коллективы : Belarussian Foundation for Basic Research [F18R-159]; Russian Foundation Basic Research [18-52-00017 Bel_a, 16-02-00507, 18-52-00020]; Council on grants of the President of the Russian Federation [SP-1844.2016.1]
Место публикации : Mater. Res. Express. - 2019. - Vol. 6, Is. 2. - Ст.026105. - ISSN 2053-1591, DOI 10.1088/2053-1591/aaef21
Примечания : Cited References: 30. - This work was supported by the Belarussian Foundation for Basic Research (project F18R-159) and Russian Foundation Basic Research (contract no. 18-52-00020). Yu S Orlov and SG Ovchinnikov are grateful Russian Foundation Basic Research (contracts no. 18-52-00017 Bel_a, 16-02-00507) and Council on grants of the President of the Russian Federation (SP-1844.2016.1) for the support.
Предметные рубрики: SPIN
NANOWIRES
Ключевые слова (''Своб.индексиров.''): neutron diffraction--orbital ordering--spin state
Аннотация: Sr1−xYxCoO2.65 (x = 0.2) with layered perovskite structure was studied by neutron diffraction, synchrotron x-ray and magnetometry methods. It is shown that in the 90–375 K temperature range the crystal structure can be described by the monoclinic space group A2/m with the superstructure 4√2a p × 2√2a p × 4a p (with a p corresponding to the unit cell parameter of the primitive cell) while basic diffraction peaks are well indexed in the space group I4/mmm (2a p × 2a p × 4a p ) shows an almost standard magnetization. The basic magnetic structure is G-type antiferromagnetic with average magnetic moments of 2.7 μ B/Co and 1.7 μ B/Co in anion-deficient CoO4+γ and stoichiometric CoO6 layers, respectively. A ferromagnetic component of about 0.27 μ B/Co is determined from the magnetization measurements at 8 K. Sr0.8Y0.2CoO2.65 shows an almost standard magnetization versus temperature dependence whereas Sr0.75Y0.25CoO2.65 exhibits an antiferromagnet-ferromagnet transition accompanied by a structural transformation. There is practically no spontaneous magnetization in x = 0.3. The type of the magnetic structure and the high value of TN suggest that the Co3+ ions are in both structural layers predominantly in the low-spin (LS)/high-spin (HS) state mixture. It is proposed that the ferromagnetic component is due to the orbital ordering occurring at TN in the CoO5 pyramids and the concomitant appearance of ferromagnetic coupling between the Co3+(HS) ions located in these CoO5 pyramids in the anion-deficient CoO4+γ layer.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

13.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Martynov S. N.
Заглавие : Field-induced helical magnetic structure in the two-subsystem frustrated antiferromagnet
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.23PO-12-17. - p.521
Примечания : Библиогр.: 2
Читать в сети ИФ
Найти похожие

14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Moshkina E. M., Eremin E. V., Molokeev M. S., Kokh, Dieter, Krylov A. S.
Заглавие : Flux growth and Raman spectroscopy study of Cu2CrBO5 crystals
Колич.характеристики :15 с
Место публикации : Crystals. - 2023. - Vol. 13, Is. 10. - Ст.1415. - ISSN 20734352 (eISSN), DOI 10.3390/cryst13101415
Примечания : Cited References: 24. - The study was supported by a grant from the Russian Science Foundation and the Krasnoyarsk Regional Science Foundation No. 22-12-20019; https://rscf.ru/project/22-12-20019/
Аннотация: Multicomponent flux systems based on both Li2WO4-B2O3-Li2O-CuO-Cr2O3 and Bi2O3-MoO3-B2O3-Na2O-CuO-Cr2O3 were studied in order to grow Cu2CrBO5 crystals. The conditions for Cu2CrBO5 crystallization were investigated by varyingthe component ratios, and the peculiarities of their interaction were characterized by studying the formation sequence of high-temperature crystallizing phases. Special attention was paid to the problem of Cr2O3 solubility. Phase boundaries between CuCrO2, Cu2CrO4, and Cu2CrBO5 were considered. The crystal structure of the obtained samples was studied viasingle crystal and powder X-ray diffraction. The chemical composition of the grown crystals was examined using the EDX technique. Anactual ratio of Cu:Cr = 1.89:1.11 was found for Cu2CrBO5 grown from the lithium-tungstate system, which showed a small deviation from 2:1, implying the presence of a part of bivalent Cr2+ in the samples. Anomalies in the thermal dependence of magnetization were analyzed and compared with the previously obtained data for Cu2CrBO5. The anomaly at TC ≈ 42 K and the antiferromagnetic phase transition at TN ≈ 119 K were considered. Polarized Raman spectra of Cu2CrBO5 were obtained for the first time, and a comparative analysis of the obtained data with other monoclinic and orthorhombic ludwigites is presented. Along with the polarized room temperature spectra, the thermal evolution of Raman modes near the antiferromagnetic phase transition temperature TN ≈ 119 K is provided. The influence of the magnetic phase transition on the Raman spectra of Cu2CrBO5 is discussed.
Смотреть статью,
Scopus,
WOS
Найти похожие

15.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Roessli B., Schefer J., Petrakovskii G. A., Ouladdiaf B., Boehm M., Staub U., Vorotinov A. M., Bezmaternikh L. N.
Заглавие : Formation of a magnetic soliton lattice in copper metaborate
Место публикации : Phys. Rev. Lett.: AMERICAN PHYSICAL SOC, 2001. - Vol. 86, Is. 9. - P1885-1888. - ISSN 0031-9007, DOI 10.1103/PhysRevLett.86.1885
Примечания : Cited References: 26
Предметные рубрики: SPIN-WAVES
BA2CUGE2O7
TRANSITION
ANTIFERROMAGNET
CUGEO3
PHASE
Ключевые слова (''Своб.индексиров.''): anisotropy--antiferromagnetism--ground state--magnetic moments--magnetic properties--magnetization--neutron diffraction--neutron scattering--phase transitions--solitons--thermal effects--antiferromagnetic state--copper metaborate--higher order magnetic satellites--magnetic soliton lattice--magnetic structure--copper compounds
Аннотация: The magnetic ground state of CuB2O4 is incommensurate at T = 1.8 K and undergoes a continuous phase transition to a noncollinear commensurate antiferromagnetic state at T* similar to 10 K. Close to T* higher-order magnetic satellites are observed. Coexistence of long- and short-range magnetic order is observed in both magnetic phases. This suggests that the association of the Dzyaloshinskii-Moriya interaction and anisotropy leads to the formation of a magnetic soliton lattice.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

16.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ovchinnikov S. G., Shneyder E. I., Korshunov M. M.
Заглавие : From underdoped to overdoped cuprates: two quantum phase transitions
Разночтения заглавия :авие SCOPUS: From underdoped to overdoped cuprates: Two quantum phase transitions
Место публикации : J. Phys.: Condens. Matter: IOP PUBLISHING LTD, 2011. - Vol. 23, Is. 4. - Ст.45701. - ISSN 0953-8984, DOI 10.1088/0953-8984/23/4/045701
Примечания : Cited References: 58. - We would like to thank S Sakai for useful discussions. The authors acknowledge support by the Russian Foundation for Basic Research (grant N 09-02-00127), by the Integration Program of SBRAS N40, the Presidium RAS Program 5.7, President of Russia (grant MK-1683.2010.2), FCP Scientific and Research-and-Educational Personnel of Innovative Russia for 2009-2013 (GK P891), and in part by the National Science Foundation under grant NSF PHY05-51164.
Предметные рубрики: HIGH-TEMPERATURE SUPERCONDUCTORS
T-J MODEL
CORRELATED FERMION SYSTEMS
VALENCE BOND STATE
MEAN-FIELD-THEORY
CRITICAL-POINT
HEISENBERG-ANTIFERROMAGNET
EXCITATIONS
PSEUDOGAP
OSCILLATIONS
Ключевые слова (''Своб.индексиров.''): critical concentration--critical points--cuprates--density of state--fermi surface topology--hall effect measurement--high-t--optimal doping--overdoped--pseudo-gap--quantum phase transitions--theoretical study--copper compounds--hall effect--magnetic field effects--phase diagrams--phase transitions
Аннотация: Several experimental and theoretical studies indicate the existence of a critical point separating the underdoped and overdoped regions of the high-T-c cuprates' phase diagram. There are at least two distinct proposals on the critical concentration and its physical origin. The first one is associated with the pseudogap formation for p p*, with p* approximate to 0.2. The other relies on the Hall effect measurements and suggests that the critical point and the quantum phase transition (QPT) take place at optimal doping, p(opt) approximate to 0.16. Here we have performed a precise density of states calculation and found that there are two QPTs and the corresponding critical concentrations associated with the change of the Fermi surface topology upon doping.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

17.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Martynov S. N., Balaev A. D.
Заглавие : Frustration mechanism of formation of a helical magnetic structure in the CuB2O4 two-subsystem antiferromagnet
Место публикации : JETP Letters. - 2007. - Vol. 85, Is. 12. - P.649-654. - ISSN 0021-3640, DOI 10.1134/S0021364007120132
Примечания : Cited References: 21
Предметные рубрики: PHASE 10 K
COPPER METABORATE
LATTICE
Аннотация: A new mechanism is proposed for forming an incommensurate magnetic structure of the transverse helix type owing to the removal of frustration through intersubsystem exchange in a two-subsystem antiferromagnet. The symmetry analysis of the distribution of the Dzyaloshinskii-Moriya interaction and comparison with the experimental data on the field dependence of magnetization indicate that antisymmetric exchange and competition between symmetric exchanges cannot be responsible for forming a helical magnetic structure in CuB2O4.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

18.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Martynov S. N., Tugarinov V. I.
Заглавие : Ground state of an antiferromagnet with uniform antisymmetric exchange in a magnetic field
Место публикации : JETP Letters. - 2010. - Vol. 92, Is. 2. - P.115-119. - ISSN 0021-3640, DOI 10.1134/S0021364010140092
Примечания : Cited References: 12
Предметные рубрики: INCOMMENSURATE
TRANSITION
ORDER
Аннотация: A system of two nonlinear differential equations for sublattice angles is proposed to describe the spin orientation distribution in a planar antiferromagnet with uniform antisymmetric exchange in a magnetic field. This system involves the initial symmetry of the problem and is reduced to a single delay differential equation. The solutions of this system are parameterized by the initial condition imposed on the angle of one sublattice at the hyperbolic singular point of the phase space. The numerical analysis of the stability boundary of soliton solutions demonstrates that the transition to the commensurate phase takes place outside the region where the stochastic solutions appear and is accompanied by the magnetization jump Delta m similar to 10(-1) m.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

19.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Martynov S. N.
Заглавие : Ground state of orthorombic weak antiferromagnet PbMnBO4 with frustrated single-ion anisotropy
Коллективы : Российская академия наук, Уральское отделение РАН, Институт физики металлов им. М. Н. Михеева Уральского отделения РАН, Уральский федеральный университет им. первого Президента России Б.Н. Ельцина, Российский фонд фундаментальных исследований, Euro-Asian Symposium "Trends in MAGnetism", "Trends in MAGnetism", Euro-Asian Symposium
Место публикации : Euro-asian symposium "Trends in magnetism" (EASTMAG-2019): Book of abstracts/ чл. конс. ком.: S. G. Ovchinnikov, N. V. Volkov [et al.] ; чл. прогр. ком. D. M. Dzebisashvili [et al.]. - 2019. - Vol. 1. - Ст.G.P10. - P.578-579. - ISBN 978-5-9500855-7-4 (Шифр В33/E12-125657784)
Примечания : Cited References: 2. - The study was funded by RFBR and the Government of Krasnoyarsk Territory, Krasnoyarsk Regional Fund of Science, to the research project no. 18-42-240008
Материалы симпозиума,
Читать в сети ИФ
Найти похожие

20.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Val'kov V. V., Fedoseev A. D.
Заглавие : Heat capacity and magnetoresistance of a lightly doped two-dimensional antiferromagnet in the noncollinear phase
Место публикации : Bull. Russ. Acad. Sci.: Phys. - 2013. - Vol. 77, Is. 3. - P.349-351. - ISSN 1062-8738, DOI 10.3103/S1062873813030386
Аннотация: The energy spectrum of mobile charge carriers in a two-dimensional Antiferromagnet placed in external magnetic field is analyzed. It is shown that allowing for the magnetic sublattice skew the effective mass of mobile charge carriers in a lightly doped Antiferromagnet. This affects substantially the transport and thermodynamic properties of the system. A insulator-semimetal transition is induced with external magnetic field. В© 2013 Allerton Press, Inc.
Scopus,
Смотреть статью,
Читать в сети ИФ
Найти похожие