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

Формат представления найденных документов:
полный	информационный	краткий

Отсортировать найденные документы по:
автору	заглавию	году издания	типу документа

Поисковый запрос: (<.>S=Valence<.>)

Общее количество найденных документов : 4
Показаны документы с 1 по 4

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aplesnin S. S., Romanova O. B., Har'kov A. M., Balaev D. A., Gorev M. V., Vorotynov A. M., Sokolov V. V., Pichugin A.
Заглавие : Metal–semiconductor transition in SmxMn1−xS solid solutions
Место публикации : Phys. Status Solidi B. - 2012. - Vol. 249, Is. 4. - P.812-817. - ISSN 0370-1972, DOI 10.1002/pssb.201147327
Примечания : Cited References: 27. - This study was supported by the Russian Foundation for Basic Research project No 09-02-00554_a; No 09-02-92001-NNS_a; No 11-02-98018 r_sibir_a; ADTP "Development of scientific potential of the higher school" No. 2.1.1/11763.
Предметные рубрики: Magnetic-properties
Phase-transition
SmS
Valence
Pressure
Crystal
Lattice
CeRhSb
Ключевые слова (''Своб.индексиров.''): kondo effect--metal-semiconductor transition--semiconductors--variable-valence elements
Аннотация: The electrical resistivity of the SmxMn1−xS (0.15 ≤ x ≤ 0.25) solid solutions in the temperature range of 80–300 K was measured. Minimum and maximum in the temperature dependence of the resistivity were found, respectively, at T = 220 K for x = 0.15 and at T = 100 K for x = 0.2 compounds. This behavior is explained from the result of the mobility-edge movement, the disorder being due to elastic deformation and spin density fluctuations with short-range order. Metal–semiconductor phase transition versus concentration at xc = 0.25 is observed. Resistivity is described by scattering electrons with acoustic phonon mode and with localized manganese spin. From the thermal expansion coefficient the compression of the lattice below the Néel temperature for Sm0.2Mn0.8S is found.
Смотреть статью,
Scopus,
WoS,
Читать в сети ИФ
Найти похожие

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]
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Val'kov V. V., Dzebisashvili D. M.
Заглавие : Properties of the heavy-fermion spectrum in the canted phase of antiferromagnetic intermetallides
Коллективы :
Место публикации : Theor. Math. Phys.: SPRINGER, 2010. - Vol. 162, Is. 1. - P106-125. - ISSN 0040-5779, DOI 10.1007/s11232-010-0008-4
Примечания : Cited References: 23. - This paper was supported by the Russian Foundation for Basic Research (Grant No. 07-02-00226), the Siberian Branch, Russian Academy of Sciences (Integrated Project No. 53), and the program "Strong Electron Correlations" of the Physics Division, Russian Academy of Sciences.
Предметные рубрики: PERIODIC ANDERSON MODEL
KONDO-LATTICE
VALENCE
Ключевые слова (''Своб.индексиров.''): periodic anderson model--heavy fermion--antiferromagnetism--canted phase--antiferromagnetism--canted phase--heavy fermion--periodic anderson model
Аннотация: We study the effect of the magnetic-field-induced canting of magnetic sublattices on the energy structure of heavy fermion quasiparticles in intermetallides with antiferromagnetic-type ordering. We work in the framework of an effective Hamiltonian of the periodic Anderson model in the regime of strong electron correlations. With the virtual transfers into high-energy double states taken into account, this Hamiltonian involves exchange interactions between spin moments of the f ions and the s-f-exchange coupling between the two subsystems. For a noncollinear problem geometry, we introduce a unitary transformation that allows reducing an eighth-order equation for the spectrum of heavy fermions to two fourth-order equations. We show that the quasimomentum dependence of the heavy-fermion energy changes qualitatively under the transition from the antiferromagnetic phase to a phase with a considerable canting angle emerging in an external magnetic field.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Val'kov V. V., Dzebisashvili D. M.
Заглавие : Spin-Fluctuation Renormalization of the Temperature of a Superconducting s-Phase in Rare-Earth Intermetallides
Коллективы :
Место публикации : J. Exp. Theor. Phys.: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2008. - Vol. 107, Is. 4. - P679-691. - ISSN 1063-7761, DOI 10.1134/S1063776108100166
Примечания : Cited References: 34. - This study was supported in part by the Russian Foundation for Basic Research ( project no. 07-02-00226), the Department of Physic of the Russian Academy of Sciences ( within the program "Strongly Correlated Electrons in Semiconductors, Superconductors, and Magnetic Materials"), and the Siberian Branch of the Russian Academy of Sciences ( integration project no. 3.4).
Предметные рубрики: HEAVY-FERMION SUPERCONDUCTORS
PERIODIC ANDERSON MODEL
WAVE SUPERCONDUCTIVITY
PERTURBATION-THEORY
MECHANISM
VALENCE
SYSTEMS
LATTICE
STATE
Ключевые слова (''Своб.индексиров.''): differential equations--electric conductivity--green's function--numerical analysis--rare earth elements--spin dynamics--spin fluctuations--anomalous components--critical temperatures--experimental datums--infinite systems--numerical calculations--order parameters--periodic anderson models--renormalization--s-phase--skutterudite--strong electron correlations--sub systems--superconducting states--superconductivity
Аннотация: A theory of the superconducting state with s-type symmetry of the order parameter ( the transition to this state was observed in recently discovered heavy-fermion skutterudite LaFe(4)P(12)) is developed using the periodic Anderson model in the limit of strong electron correlations. Exact representations of Green's functions of the superconducting phase via the normal and anomalous components of the mass and strength operators are obtained. It is shown that an important role in the description of this superconducting phase is played by the anomalous components of the strength operator, which reflect spin-fluctuation processes in the localized subsystem. These components are calculated in the one-loop approximation using the solution of an infinite system of integral equations of self-consistency for the superconducting phase. Numerical calculations show that allowance for the process of scattering on spin fluctuations leads to renormalization of the critical temperature and provides agreement with the experimental data.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие