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Каталог книг и брошюр библиотеки ИФ СО РАН

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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Avramov P. V., Sakai S., Entani S., Matsumoto Y., Naramoto, Hiroshi
Заглавие : Ab initio LC-DFT study of graphene, multilayer graphenes and graphite
Место публикации : Chem. Phys. Lett.: Elsevier Science BV, 2011. - Vol. 508, Is. 1-3. - P.86-89. - ISSN 0009-2614, DOI 10.1016/j.cplett.2011.04.016
Примечания : Cited References: 32. - This work was supported by JAEA Research fellowship (P.V.A.). P.V.A. also acknowledges JAEA ASRC and Molecular Spintronics Group for hospitality and fruitful collaboration.
Предметные рубрики: DENSITY
NANORIBBONS
PERFORMANCE
FUNCTIONALS
FULLERENE
COBALT
FILMS
Аннотация: Atomic structure of graphene, bi-, tri-, tetralayer graphenes and graphite as well was studied using ab initio HSE, LDA and PBE DFT approaches in periodic boundary conditions. Based on comparison of theoretical results with experimental data the performance of the methods was estimated. It was found that long-range corrected HSE potential is the most reliable DFT approximation to reproduce the atomic structure of weakly bound multilayer graphenes and graphite as well. (C) 2011 Elsevier B. V. All rights reserved.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Balaev D. A., Gokhfeld D. M., Popkov S. I., Shaikhutdinov K. A., Klinkova L. A., Zherikhina L. N., Tsvokhrebov A. M.
Заглавие : Increase in the magnetization loop width in the Ba0.6K0.4BiO3 superconductor: Possible manifestation of phase separation
Место публикации : J. Exp. Theor. Phys.: MAIK Nauka-Interperiodica / Springer, 2014. - Vol. 118, Is. 1. - P.104-110. - ISSN 1063-7761, DOI 10.1134/S1063776114010038. - ISSN 1090-6509
Примечания : Cited References: 39
Предметные рубрики: (K,BA)BIO3 SINGLE-CRYSTALS
II SUPERCONDUCTORS
BISMUTH-OXIDE
PEAK
DENSITY
TC
Аннотация: The magnetization of Ba0.6K0.4BiO3 samples in fields up to 90 kOe in the temperature range from 2 to 30 K is investigated. It is shown that the observed increase in the width of the magnetization loop can be explained by a decrease in the phase nonuniformity upon an increase in the magnetic field. The asymmetric hysteretic dependence of magnetization with the secondary peak was successfully described by the extended critical state model taking into account the phase separation in the superconductor.
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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 superconductivity in idealized doped graphene
Коллективы : Program of the Division of Physical Sciences of the Russian Academy of Sciences [11.3.1]; Russian Foundation for Basic Research [14-02-00058, 14-02-31237]; Council of the President of the Russian Federation [MK-526.2013.2]; Dynasty Foundation
Место публикации : Solid State Commun.: PERGAMON-ELSEVIER SCIENCE LTD, 2014. - Vol. 188. - P.61-66. - ISSN 0038-1098, DOI 10.1016/j.ssc.2014.03.001. - ISSN 1879-2766
Примечания : Cited References: 31. - This work was supported by the Program of the Division of Physical Sciences of the Russian Academy of Sciences (Project 11.3.1), and the Russian Foundation for Basic Research (Projects 14-02-00058 and 14-02-31237). One of the authors (M.M.K.) acknowledges the support of the Council of the President of the Russian Federation (Project MK-526.2013.2), and the Dynasty Foundation.
Предметные рубрики: REPULSIVE INTERACTIONS
HUBBARD-MODEL
SUPERFLUIDITY
INSTABILITY
MECHANISM
DENSITY
SYSTEMS
Ключевые слова (''Своб.индексиров.''): graphene--superconductivity
Аннотация: Idealized graphene monolayer is considered neglecting the van der Waals potential of the substrate and the role of the nonmagnetic impurities. The effect of the long-range Coulomb repulsion in an ensemble of Dirac fermions on the formation of the superconducting pairing in a monolayer is studied in the framework of the Kohn-Luttinger mechanism. The electronic structure of graphene is described in the strong coupling Wannier representation on the hexagonal lattice. We use the Shubin-Vonsowsky model which takes into account the intra- and intersite Coulomb repulsions of electrons. The Cooper instability is established by solving the Bethe-Salpeter integral equation, in which the role of the effective interaction is played by the renormalized scattering amplitude. The renormalized amplitude contains the Kohn-Luttinger polarization contributions up to and including the second-order terms in the Coulomb repulsion. We construct the superconductive phase diagram for the idealized graphene monolayer and show that the Kohn-Luttinger renormalizations and the intersite Coulomb repulsion significantly affect the interplay between the superconducting phases with f-, d+id-, and p+ip-wave symmetries of the order parameter. (C) 2014 Elsevier Ltd. All rights reserved.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gokhfel'd D. M., Balaev D. A., Semenov S. V., Petrov M. I.
Заглавие : Magnetoresistance anisotropy and scaling in textured high-temperature superconductor Bi1.8Pb0.3Sr1.9Ca2Cu3Ox
Место публикации : Phys. Solid State: MAIK Nauka-Interperiodica / Springer, 2015. - Vol. 57, Is. 11. - P.2145-2150. - ISSN 1063-7834, DOI 10.1134/S1063783415110128
Примечания : Cited References: 29
Предметные рубрики: ELECTRIC-POWER APPLICATIONS
TRANSPORT CRITICAL-CURRENT
T-C
SINGLE-CRYSTALS
TAPES
DISSIPATION
BOUNDARIES
DENSITY
FIELD
Аннотация: The magnetoresistance of the textured high-temperature superconductor (HTSC) Bi1.8Pb0.3Sr1.9Ca2Cu3Ox + Ag has been studied at different directions of the transport current I and external magnetic field H with respect to crystallographic directions of HTSC crystallites. When I and H are oriented along the ab planes of crystallites and φ is the angle between H and I, the anisotropic part of the magnetoresistance follows the functional dependence sin2φ, which is characteristic of vortex flows under Lorentz forces. The magnetoresistance R at H parallel to the c axis of crystallites (H || c) is higher than R at H || ab for both cases of I || c and I || ab. The anisotropy coefficient γ ≈ 2.3 has been estimated from the scaling of the dependences R(H) measured at H || c and H || ab. The inclusion of the magnetic field induced by the transport current allows scaling of the dependences R(H) at different values of I. A qualitative picture of the current flow along the c axis of crystallites in the textured HTSC has been proposed. © 2015, Pleiades Publishing, Ltd.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ignatchenko V. A., Tsikalov D. S.
Заглавие : Green's functions of the scalar model of electromagnetic fields in sinusoidal superlattices
Место публикации : Physica B: Elsevier, 2016. - Vol. 485. - P.94-102. - ISSN 09214526 (ISSN), DOI 10.1016/j.physb.2016.01.006
Примечания : Cited References: 30
Предметные рубрики: SCATTERING
MEDIA
PROPAGATION
GRATINGS
DENSITY
LIGHT
Ключевые слова (''Своб.индексиров.''): green's functions--electromagnetic waves--scalar model--sinusoidal superlattices--photonic crystals--ldos
Аннотация: Problems of obtaining Green's function and using it for studying the structure of scalar electromagnetic fields in a sinusoidal superlattice are considered. An analytical solution of equation in the k-space for Green's function is found. Green's function in the r-space is obtained by both the numerical and the approximate analytical Fourier transformation of that solution. It is shown, that from the experimental study of Green's function in the k-space the position of the plane radiation source relative to the extremes of the dielectric permittivity ?(z) can be determined. The relief map of Green's function in the r-space shows that the structure of the field takes the form of chains of islets in the plane ?z, the number of which increases with increasing the distance from a radiation source. This effect leads to different frequency dependences of Green's function at different distances from the radiation source and can be used to measure the distance to the internal source. The real component of Green's function and its spatial decay in the forbidden zones in the near field is investigated. The local density of states, depending on the position of the source in the superlattice, is calculated.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kagan M. Y., Mitskan V. A., Korovushkin M. M.
Заглавие : High-Tc and Low-Tc superconductivity in electron systems with repulsion
Коллективы : Russian Foundation for Basic Research [14-02-00058, 14-02-31237]; Basic Research Program of the National Research University Higher School of Economics; Dynasty foundation; [SP-1361.2015.1]
Место публикации : J. Supercond. Nov. Magn.: Springer, 2016. - Vol. 29, Is. 4. - P.1043-1048. - ISSN 1557-1939, DOI 10.1007/s10948-016-3384-7. - ISSN 1557-1947(eISSN)
Примечания : Cited References:31. - The authors are grateful to V. V. Val'kov, I. S. Burmistrov, M. V. Feigel'man, and A. Ya. Tzalenchuk for valuable remarks. This work is supported by the Russian Foundation for Basic Research (nos. 14-02-00058 and 14-02-31237). One of the authors (M. Yu. K.) gratefully acknowledges support from the Basic Research Program of the National Research University Higher School of Economics. Another one (M. M. K.) thanks the scholarship SP-1361.2015.1 of the President of Russia and the Dynasty foundation.
Предметные рубрики: Fermion systems
Doped graphene
Hubbard-model
Phase-diagram
Superfluidity
Density
Ключевые слова (''Своб.индексиров.''): unconventional superconductivity--kohn-luttinger mechanism--graphene
Аннотация: We demonstrate the instability of the normal state of purely repulsive fermionic systems towards the transition to the Kohn-Luttinger superconducting state. We construct the superconducting phase diagrams of these systems in the framework of the Hubbard and Shubin-Vonsovsky models on the square and hexagonal lattices. We show that an account for the long-range Coulomb interactions, as well as the Kohn- Luttinger renormalizations, lead to an increase in the critical superconducting temperatures in various materials, such as high-temperature superconductors, idealized monolayer, and bilayer of doped graphene. Additionally, we discuss the role of the structural disorder and the nonmagnetic impurities in superconducting properties of real graphene systems.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Val'kov V. V., Dzebisashvili D. M., Korovushkin M. M., Barabanov A. F.
Заглавие : Stability of the superconducting dx2-y2 phase in high-Tc superconductors with respect to the intersite coulomb repulsion of holes at oxygen
Коллективы : Russian Foundation for Basic Research [16-02-00073, 16-02-00304]; Dynasty Foundation; Council of the President of the Russian Federation for Support of Young Scientists and Leading Scientific Schools [SP-1361.2015.1]
Место публикации : JETP Letters. - 2016. - Vol. 103, Is. 6. - P.385-389. - ISSN 0021-3640, DOI 10.1134/S0021364016060114. - ISSN 1090-6487(eISSN)
Примечания : Cited References:28. - This work was supported by the Russian Foundation for Basic Research, project nos. 16-02-00073 and 16-02-00304. The work of D.D.M. and M.M.K. was supported by the Dynasty Foundation and the work of M.M.K. was also supported by the Council of the President of the Russian Federation for Support of Young Scientists and Leading Scientific Schools (project no. SP-1361.2015.1).
Предметные рубрики: Hubbard-model
Spin polaron
Density
Аннотация: It has been shown that, because of the two-orbital character of the subsystem of holes located at oxygen sites and the spatial separation of this subsystem from that of spins at copper ions, the superconducting phase in high-Tc superconductors is stable with respect to the strong Coulomb repulsion of holes located at nearestneighbor oxygen sites if the order parameter has the dx2−y2 symmetry. This effect is due to the symmetry characteristics of the Coulomb potential, owing to which the equation determining the Cooper pairing in the dx2−y2 channel does not include this potential.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Efremov D. V., Korshunov M. M., Dolgov O. V., Golubov A. A., Hirschfeld P. J.
Заглавие : Disorder-induced transition between s(+/-) and s(++) states in two-band superconductors
Разночтения заглавия :авие SCOPUS: Disorder-induced transition between sВ± and s++ states in two-band superconductors
Место публикации : Phys. Rev. B: AMER PHYSICAL SOC, 2011. - Vol. 84, Is. 18. - Ст.180512. - ISSN 1098-0121, DOI 10.1103/PhysRevB.84.180512
Примечания : Cited References: 31. - The authors are grateful to S.-L. Drechsler, P. Fulde, I. I. Mazin, V. Mishra, and D. J. Scalapino for useful discussions. The present work was partially supported by the DFG Priority Programme SPP1458 (D.V.E.), Dutch FOM(A.A.G.), DOEDE-FG02-05ER46236 (P.J.H. and M.M.K.), and RFBR 09-02-00127, Presidium of RAS program N5.7, FCP GK P891, and GK 16.740.12.0731, and President of Russia MK-1683.2010.2 (M.M.K.). P.J.H. and M.M.K. are grateful for the support of the Kavli Institute for Theoretical Physics and the Stanford Institute for Materials & Energy Science during the writing of this work.
Предметные рубрики: HIGH-TEMPERATURE SUPERCONDUCTIVITY
IMPURITIES
DENSITY
Аннотация: We have reexamined the problem of disorder in two-band superconductors, and shown, within the framework of the T-matrix approximation, that the suppression of T-c can be described by a single parameter depending on the intraband and interband impurity scattering rates. T-c is shown to be more robust against nonmagnetic impurities than would be predicted in the trivial extension of Abrikosov-Gor'kov theory. We find a disorder-induced transition from the s(+/-) state to a gapless and then to a fully gapped s(++) state, controlled by a single parameter-the sign of the average coupling constant (lambda). We argue that this transition has strong implications for experiments.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Altin S., Gokhfeld D. M.
Заглавие : Magnetization loops and pinning force of Bi-2212 single-crystal whiskers
Место публикации : Physica C. - 2011. - Vol. 471, Is. 7-8. - P.217-221. - ISSN 0921-4534, DOI 10.1016/j.physc.2011.01.006
Примечания : Cited References: 40. - The work is supported by Project No. 7 of RAS Program "Quantum physics of condensed matter", Grant No. 13 of Lavrentyev competition of young researchers of SB RAS and Scientific and Technical Research Council of Turkey (TUBITAK) under Contract No. TUBITAK-109T747.
Предметные рубрики: T-C SUPERCONDUCTORS
HIGH-TEMPERATURE SUPERCONDUCTORS
JOSEPHSON VORTICES
GROWTH
BI2SR2CACU2O8+DELTA
DENSITY
STATE
FIELD
MELT
Ключевые слова (''Своб.индексиров.''): bi-2212--whisker--magnetization loop--pinning force--extended critical state model--bi-2212--extended critical state model--magnetization loop--pinning force--whisker--bi-2212--extended critical state model--magnetization loop--pinning force--whisker--flux pinning--magnetic fields--magnetization--critical current density (superconductivity)
Аннотация: Dependence of magnetization on applied magnetic field for single-crystal Bi-2212 whiskers was measured at different temperatures. Symmetric and asymmetric magnetization loops were successfully described by the extended critical state model (the extended Valkov-Khrustalev model). Pinning force of whiskers was investigated. (C) 2011 Elsevier B.V. All rights reserved.
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10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kagan M. Y., Valkov V. V.
Заглавие : Anomalous resistivity and superconductivity in the two-band Hubbard model with one narrow band (Review)
Место публикации : Low Temp. Phys. - 2011. - Vol. 37, Is. 1. - P.69-82. - ISSN 1063-777X, DOI 10.1063/1.3552118; \b Физика низких температур
Примечания : Cited References: 62. - We thank A.S. Alexandrov, A.F. Andreev, M.A. Baranov, Yu. Bichkov, A.V. Chubukov, D.V. Efremov, A.S. Hewson, K.A. Kikoin, F.V. Kusmartsev, P. Nozieres, T.M. Rice, A.O. Sboychakov, P. Thalmeer, C.M. Varma, D. Vollhardt, P. Woelfle, A. Yaresko and, especially, P. Fulde, Yu. Kagan, K.I. Kugel, and N.V. Prokof'ev for many simulating discussions on this subject and acknowledge the financial support of RFBR grants # 08-02-00224 and 08-02-00212. M.Yu.K. is also grateful to the Leverhulme trust for a grant to visit Loughborough University, where this work was completed.
Предметные рубрики: FERMI-LIQUID BEHAVIOR
MAGNETIC-ALLOYS
HEAVY
DENSITY
SYSTEMS
STATE
UPT3
MECHANISM
PARTICLE
VALENCE
Аннотация: We search for marginal Fermi-liquid behavior in the two-band Hubbard model with one narrow band. We consider the limit of low electron densities in the bands and strong intraband and interband Hubbard interactions. We analyze the influence of electron-polaron effects and other mechanisms for mass-enhancement (related to the momentum dependence of the self-energies) on the effective mass and scattering times of light and heavy components in the clean case (electron-electron scattering and no impurities). We find a tendency towards phase separation (towards negative partial compressibility of heavy particles) in the 3D case with a large mismatch between the densities of heavy and light bands in the strong coupling limit. We also find that for low temperatures and equal densities, the resistivity in a homogeneous state R(T) proportional to T-2 behaves as a Fermi-liquid in both 3D and 2D. For temperatures greater than the effective bandwidth for heavy electrons T W-h*, the coherence of the heavy component breaks down completely. The heavy particles move diffusively in the surrounding light particles. At the same time, light particles scatter on heavy particles as if on immobile (static) impurities. Under these conditions, the heavy component is marginal, while the light component is not. The resistivity approaches saturation for T W-h* in the 3D case. In 2D the resistivity has a maximum and a localization tail owing to weak-localization corrections of the Altshuler-Aronov type. This behavior of resistivity in 3D could be relevant for some uranium-based heavy-fermion compounds such as UNi2Al3 and in 2D, for some other mixed-valence compounds, possibly including layered manganites. We also consider briefly the superconductive (SC) instability in this model. The leading instability tends to p-wave pairing and is governed by an enhanced Kohn-Luttinger mechanism for SC at low electron densities. The critical temperature corresponds to the pairing of heavy electrons via polarization of the light electrons in 2D. (C) 2011 American Institute of Physics. [doi:10.1063/1.3552118]
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