Главная
Авторизация
Фамилия
Пароль
 

Базы данных


Труды сотрудников ИФ СО РАН - результаты поиска

Вид поиска

Область поиска
в найденном
Формат представления найденных документов:
полный информационныйкраткий
Отсортировать найденные документы по:
авторузаглавиюгоду изданиятипу документа
Поисковый запрос: (<.>S=SPECTRUM<.>)
Общее количество найденных документов : 36
Показаны документы с 1 по 10
 1-10    11-20   21-30   31-36 
1.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aksenov S. V., Zlotnikov A. O., Shustin M. S.
Заглавие : Strong Coulomb interactions in the problem of Majorana modes in a wire of the nontrivial topological class BDI
Коллективы : RAS Presidium programs for fundamental research [32, 12]; Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR) [18-32-00443, 19-02-00348]; Government of Krasnoyarsk Territory, Krasnoyarsk Regional Fund of Science [19-42-240011]; Council of the President of the Russian Federation for Support of Young Scientists and Leading Scientific SchoolsLeading Scientific Schools Program [MK-1641.2020.2, MK-3594.2018.2]; Foundation for the Advancement of Theoretical Physics and Mathematics "BASIS" [18-46-007]
Место публикации : Phys. Rev. B. - 2020. - Vol. 101, Is. 12. - Ст.125431. - ISSN 2469-9950, DOI 10.1103/PhysRevB.101.125431. - ISSN 2469-9969(eISSN)
Примечания : Cited References: 60. - We acknowledge fruitful discussions with V. V. Valkov and V. A. Mitskan. The reported study was funded by the RAS Presidium programs for fundamental research Nos. 12 and 32, Russian Foundation for Basic Research (Projects No. 18-32-00443 and No. 19-02-00348), Government of Krasnoyarsk Territory, Krasnoyarsk Regional Fund of Science to the research project: "Coulomb interactions in the problem of Majorana modes in low-dimensional systems with nontrivial topology" (Grant No. 19-42-240011). S.V.A. and A.O.Z. are grateful to the Council of the President of the Russian Federation for Support of Young Scientists and Leading Scientific Schools, Projects No. MK-1641.2020.2 and No. MK-3594.2018.2. S.V.A. acknowledges the support from the Foundation for the Advancement of Theoretical Physics and Mathematics "BASIS" (Grant No. 18-46-007).
Предметные рубрики: QUANTUM
POLARIZATION
TRANSITION
FERMIONS
SPECTRUM
STATE
Аннотация: In this study, the problem of strong Coulomb interactions in topological superconducting wire is analyzed by means of the density-matrix-renormalization-group (DMRG) approach. To analyze properties of edge states in the BDI-class structure, a quantity called Majorana polarization is used. From its dependence on wire length and an entanglement-spectrum degeneracy, topological phase diagrams are obtained. The DMRG calculations for the Shubin-Vonsovsky-type model of the wire show the transformation of phases with Majorana single and double modes (MSMs and MDMs, respectively) under the increase of onsite and intersite correlations. In particular, we demonstrate different scenarios including the possibilities of both induction and suppression of the MSMs and MDMs. It is shown that in the strongly correlated regime, the contributions of single-particle excitations to the Majorana-type states significantly decrease at low magnetic fxields. Moreover, the t-J*-V model is derived allowing to study the effective interactions and improve the DMRG numerics. It is found out that in the limiting case of the effective Hamiltonian with infinitely strong onsite repulsion, t model, the topological phases are destroyed. Finally, the ways to probe the MSMs and MDMs via the features of caloric functions are discussed.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
2.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Iskhakov R. S., Stolyar S. V., Chekanova L. A., Vazhenina I. G.
Заглавие : Spin-Wave Resonance in One-Dimensional Magnonic Crystals by an Example of Multilayer Co-P Films
Место публикации : Phys. Solid State. - 2020. - Vol. 62, Is. 10. - P.1861-1867. - ISSN 1063-7834, DOI 10.1134/S1063783420100121. - ISSN 1090-6460(eISSN)
Примечания : Cited References: 47
Предметные рубрики: FERROMAGNETIC-RESONANCE
SPECTRUM
MODES
INHOMOGENEITIES
Аннотация: Layered magnetic films of Co–P alloy, which are sets of laminates with certain atomic and chemical structures, have been investigated by spin-wave resonance. Coatings of two types were synthesized: a magnonic crystal (amorphous Co(P)/fcc Co(P))N and gradient Co(P) films. They exhibit two different modifications of the spin-wave resonance (SWR) spectrum. In the first case, the SWR spectrum is described as Hn(n) ~ n2 with a modification caused by the formation of the first stop band of the magnonic crystal. In the second case, the dependence of resonance fields Hn of the spin-wave modes on mode number n has the form of Hn(n) ~ n2/3. Thermal annealing leads to crystallization (amorphous alloy → fcc) and causes transformation of the layered films to the films of single-phase Co–P alloys, which is accompanied by a change in the shapes of the SWR spectra and occurrence of a “exchange kink” spectral modification.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
3.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Vazhenina I. G., Iskhakov R. S., Milyaev M. A., Naumova L. I., Rautskii M. V.
Заглавие : Spin Wave Resonance in the [(Co0.88Fe0.12)/Cu]N Synthetic Antiferromagnet
Коллективы : Ministry of Science and Higher Education of the Russian Federation [AAAA-A18-118020290104-2]; Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR) [20-42-660018]
Место публикации : Tech. Phys. Lett. - 2020. - Vol. 46, Is. 11. - P.1076-1079. - ISSN 1063-7850, DOI 10.1134/S1063785020110140. - ISSN 1090-6533(eISSN)
Примечания : Cited References: 19. - This study was carried out under a state order of the Ministry of Science and Higher Education of the Russian Federation (theme "Spin" no. AAAA-A18-118020290104-2) and supported in part by the Russian Foundation for Basic Research (project no. 20-42-660018)
Предметные рубрики: MAGNETIC-PROPERTIES
MAGNETORESISTANCE
SPECTRUM
FILMS
Аннотация: The [(Co0.88Fe0.12)/Cu]N synthetic antiferromagnet has been investigated by the spin wave resonance method over the entire range of angles of an external dc magnetic field to the film surface normal. The investigations have shown that the superlattice under study consists of two exchange-coupled magnetic subsystems, each manifested in the recorded spectra as a series of spin-wave modes. The dependence of the linear region of propagation of a standing spin-wave mode on the sample orientation in an external magnetic field has been established.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
4.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gorelik V. S., Pyatyshev, A. Yu., Krylov A. S.
Заглавие : Raman light scattering in sodium nitrite crystals
Коллективы : Russian Foundation for Basic Research [12-02-00491, 13-02-00449, 13-02-90420, 14-02-00190]
Место публикации : Bull. Lebedev Phys. Inst.: Allerton Press, 2016. - Vol. 43, Is. 5. - P.167-173. - ISSN 1068-3356, DOI 10.3103/S1068335616050043. - ISSN 1934-838X(eISSN)
Примечания : Cited References:37. - This study was supported by the Russian Foundation for Basic Research, projects nos. 12-02-00491, 13-02-00449,13-02-90420, 14-02-00190.
Предметные рубрики: NANO2
PHASE
SPECTROSCOPY
PARAPHOTONS
DEPENDENCE
SPECTRUM
SEARCH
Ключевые слова (''Своб.индексиров.''): sodium nitrite--raman scattering--spectrum--polar mode--polariton--ferroelectric--dispersion curves
Аннотация: Raman light scattering spectra of a ferroelectric sodium nitrite crystal is studied in the lattice mode region as the temperature is lowered from room temperature to 123 K. The existence of a Raman satellite corresponding to the soft lattice mode, i.e., transverse polar vibration responsible for the ferroelectric phase transition, is established for the first time. It is found that the intensity of the Raman scattering by the pseudo-scalar low-frequency A (2) mode exceeds the intensity of other lattice variations by an order of magnitude.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
5.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Klimin S. A., Kashchenko M. A., Bezmaternykh L. N.
Заглавие : Spin-phonon and electron-phonon interactions in multiferroic GdFe3(BO3)4 and TbFe3(BO3)4 evidenced by IR reflection spectroscopy
Коллективы : Russian Science Foundation [14-12-01033]; Swiss National Science Foundation (SNSF); Science and Technology cooperation program "Switzerland-Russia" of the University of Geneva
Место публикации : J. Low Temp. Phys.: Springer/Plenum Publishers, 2016. - Vol. 185, Is. 5-6. - P.538-543. - ISSN 0022-2291, DOI 10.1007/s10909-016-1597-6. - ISSN 1573-7357(eISSN)
Примечания : Cited References:19. - The authors thank Alexey Kuzmenko and Marina Popova for fruitful discussions. This paper was supported by the Russian Science Foundation under Grant No. 14-12-01033, by the Swiss National Science Foundation (SNSF), and by the Science and Technology cooperation program "Switzerland-Russia" of the University of Geneva.
Предметные рубрики: PHASE-TRANSITIONS
GdFe3(BO3)4
CRYSTALS
SPECTRUM
Ключевые слова (''Своб.индексиров.''): multiferroics--ir-active phonons--spin-phonon interaction--coupled--electron-phonon mode
Аннотация: We study temperature-dependent polarized reflection spectra of multiferroic GdFe3(BO3)4 and TbFe3(BO3)4 single crystals. Signatures of spin–lattice interactions in both compounds and of a formation of the electron–phonon coupled mode in TbFe3(BO3)4 are discussed.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
6.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gorelik V. S., Pyatyshev A. Y., Krylov A. S.
Заглавие : Raman scattering in sodium nitrite crystals near the phase transition
Место публикации : Phys. Solid State: MAIK Nauka-Interperiodica / Springer, 2016. - Vol. 58, Is. 1. - P.170-176. - ISSN 10637834 (ISSN), DOI 10.1134/S1063783416010133
Примечания : Cited References: 39. - This study was supported by the Russian Foundation for Basic Research (project nos. 12-02-00491, 13-02-00449, 13-02-90420, and 14-02-00190).
Предметные рубрики: NaNO2
SPECTROSCOPY
DEPENDENCE
SPECTRUM
SEARCH
MODES
Аннотация: Optical Raman spectra of a ferroelectric sodium nitrite crystal have been detected in a wide spectrum range at various temperatures, including the region of the ferroelectric phase transition. A manifestation of a transverse soft polar mode of the A1(z) type responsible for the ferroelectric phase transition has been discovered in the spectrum at room temperature. This mode has been found to become overdamped even far from the ferroelectric phase transition temperature. This mode also appears as a central peak under heating. It has been found that the pseudoscalar mode of the A2 type has the highest intensity in the Raman spectrum of sodium nitrite. The frequency corresponding to the maximum intensity of this mode in the Raman spectrum varies from 130 cm–1 at 123 K to 106 cm–1 at T = 513 K. A fair agreement of the experimental data for the A1(z) mode with the Lyddane–Sachs–Teller relation has been established. The polariton curves for the A1(z) polar mode and the dispersion curves for axinons has been plotted. © 2016, Pleiades Publishing, Ltd.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
7.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Makarov I. A., Ovchinnikov S. G.
Заглавие : Temperature dependence of the electronic structure of La2CuO4 in the multielectron LDA+GTB approach
Место публикации : J. Exp. Theor. Phys.: MAIK Nauka-Interperiodica / Springer, 2015. - Vol. 121, Is. 3. - P.457-464. - ISSN 1063-7761, DOI 10.1134/S1063776115090174
Примечания : Cited References: 38. - The work was supported by the Russian Science Foundation (project no. 14-12-00061)
Предметные рубрики: Copper oxides
Model
Superconductivity
Excitations
Instability
Spectrum
States
Order
Аннотация: The band structure of La2CuO4 in antiferromagnetic and paramagnetic phases is calculated at finite temperatures by the multielectron LDA+GTB method. The temperature dependence of the band spectrum and the spectral weight of Hubbard fermions is caused by a change in the occupation numbers of local multielectron spin-split terms in the antiferromagnetic phase. A decrease in the magnetization of the sublattice with temperature gives rise to new bands near the bottom of the conduction band and the top of the valence band. It is shown that the band gap decreases with increasing temperature, but La2CuO4 remains an insulator in the paramagnetic phase as well. These results are consistent with measurements of the red shift of the absorption edge in La2CuO4 with increasing temperature. © 2015, Pleiades Publishing, Inc.
Смотреть статью,
Scopus,
WOS,
РИНЦ,
Читать в сети ИФ
Найти похожие
8.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kagan M. Y., Val'kov V. V., Mitskan V. A., Korovushkin M. M.
Заглавие : The Kohn-Luttinger effect and anomalous pairing in new superconducting systems and graphene
Коллективы : Physics Department of the Russian Academy of Sciences [P.3.1]; Russian Foundation for Basic Research [14-02-00058, 14-02-31237]; Russian Federation [MK-526.2013.2]; Dynasty Foundation
Место публикации : J. Exp. Theor. Phys.: MAIK Nauka-Interperiodica / Springer, 2014. - Vol. 118, Is. 6. - P.995-1011. - ISSN 1063-7761, DOI 10.1134/S1063776114060132. - ISSN 1090-6509
Примечания : Cited References: 114. - This study was supported by the Program of the Physics Department of the Russian Academy of Sciences (project no. P.3.1) and the Russian Foundation for Basic Research (project nos. 14-02-00058 and 14-02-31237). The work of two coauthors (M. M. K. and V.A.M) was supported financially by grant no. MK-526.2013.2 of the President of the Russian Federation and the Dynasty Foundation.
Предметные рубрики: P-WAVE SUPERCONDUCTIVITY
EXTENDED HUBBARD-MODEL
NARROW ENERGY-BANDS
2D KONDO-LATTICE
FERMI GAS
REPULSIVE INTERACTIONS
ELECTRON CORRELATIONS
COOPER INSTABILITY
PHASE-DIAGRAM
SPECTRUM
Аннотация: We present a review of theoretical investigations into the Kohn-Luttinger nonphonon superconductivity mechanism in various 3D and 2D repulsive electron systems described by the Fermi-gas, Hubbard, and Shubin-Vonsovsky models. Phase diagrams of the superconducting state are considered, including regions of anomalous s-, p-, and d-wave pairing. The possibility of a strong increase in the superconducting transition temperature T c even for a low electron density is demonstrated by analyzing the spin-polarized case or the two-band situation. The Kohn-Luttinger theory explains or predicts superconductivity in various materials such as heterostructures and semimetals, superlattices and dichalcogenides, high-T c superconductors and heavy-fermion systems, layered organic superconductors, and ultracold Fermi gases in magnetic traps. This theory also describes the anomalous electron transport and peculiar polaron effects in the normal state of these systems. The theory can be useful for explaining the origin of superconductivity and orbital currents (chiral anomaly) in systems with the Dirac spectrum of electrons, including superfluid 3He-A, doped graphene, and topological superconductors.
Смотреть статью,
Scopus,
WoS,
Читать в сети ИФ
Найти похожие
9.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ovchinnikov S. G., Sidorov K. A., Shneyder E. I.
Заглавие : Anomalous thermodynamics of the doped Mott-Hubbard insulators
Место публикации : Phys. Solid State: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2011. - Vol. 53, Is. 2. - P299-302. - ISSN 1063-7834, DOI 10.1134/S1063783411020247
Примечания : Cited References: 6. - This study was supported by the Russian Foundation for Basic Research (project no. 09-02-00127), the Branch of the Physical Sciences of the Russian Academy of Sciences (program nos. 2 and 3), grant no. MK-1683.2010.2, and by the Federal Target Program "Personnel" (project NK-589 P).
Предметные рубрики: T-J MODEL
SPECTRUM
Аннотация: The concentration dependence of the entropy of doped Mott-Hubbard insulators has been considered within the t-J model. It has been shown that a change in the type and statistics of charge carriers as compared to the Fermi gas leads to a radical change in the entropy s, in particular, to the giant growth of the entropy upon doping. The quantity a,s/a,x a parts per thousand k (B) is approximately consistent with the experimental data for HTSC cuprates in the pseudogap phase.
WOS,
Scopus,
РИНЦ,
Смотреть статью,
Читать в сети ИФ
Найти похожие
10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Pisarev R. V., Kalashnikova A. M., Schops O., Bezmaternykh L. N.
Заглавие : Electronic transitions and genuine crystal-field parameters in copper metaborate CuB2O4
Разночтения заглавия :авие SCOPUS: Electronic transitions and genuine crystal-field parameters in copper metaborate CuB 2O 4
Место публикации : Phys. Rev. B: AMER PHYSICAL SOC, 2011. - Vol. 84, Is. 7. - Ст.75160. - ISSN 1098-0121, DOI 10.1103/PhysRevB.84.075160
Примечания : Cited References: 65. - Useful discussions with W. Weber on crystal-field splitting of 3d states in cuprates are appreciated. We thank H.-J. Weber for the help in using Cary 2300 spectrophotometer. This work is supported by the Russian Foundation for Basic Research (project No. 09-02-00070) and Federal Agency for Science and Innovations (Grant No. 02.740.11.0384). A. M. K. acknowledges the financial support from the Committee for Science and Higher Education of the Government of Saint Petersburg.
Предметные рубрики: OPTICAL-ABSORPTION
PHASE-DIAGRAM
CUGEO3
SPECTRUM
SUPERCONDUCTORS
EXCITATIONS
SR2CUO2CL2
SCATTERING
LA2CUO4
CUPRATE
Аннотация: We present and analyze high-resolution alpha-, sigma-, and pi-polarized absorption spectra related to d-d electronic transitions in tetragonal metaborate CuB2O4 where copper Cu2+ ions occupy two crystallographically distinct 4b and 8d positions. The spectra are characterized by exceptionally rich fine structure in the spectral range of 1.4-2.4 eV. Six zero-phonon (ZP) lines originating from the electronic transitions within the Cu2+ ions in both positions are distinguished and identified. Symmetry analysis explains polarization properties of the ZP lines in the 8d positions but only partially explains them in the 4b positions. Reliable assignment of all six ZP lines to specific transitions allowed us to calculate genuine cubic Dq and tetragonal Ds and Dt crystal-field parameters for both positions. We show that the (3r(2) - z(2)) state, the energy of which is the measure of the Jahn-Teller splitting, is the highest 3d state for both types of Cu2+ ion positions. Using the obtained crystal-field parameters as the reference values, we estimated Dq, Ds, and Dt for several other cuprates with different Cu-O bond lengths. In particular, the 3d level splitting in La2CuO4, Nd2CuO4, CuGeO3, Sr2CuO2Cl2, and Cu3B7O13Cl was analyzed. Our estimates suggest that the Jahn-Teller splitting in some of these cuprates is larger than it was assumed previously.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие
 1-10    11-20   21-30   31-36 
 

Другие библиотеки

© Международная Ассоциация пользователей и разработчиков электронных библиотек и новых информационных технологий
(Ассоциация ЭБНИТ)