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

Найдено в других БД:

Каталог книг и брошюр библиотеки ИФ СО РАН (304)

Каталог журналов библиотеки ИФ СО РАН (5)

Формат представления найденных документов:
полный	информационный	краткий

Отсортировать найденные документы по:
автору	заглавию	году издания	типу документа

Поисковый запрос: (<.>K=theory<.>)

Общее количество найденных документов : 260
Показаны документы с 1 по 20

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Heller Y. I.
Заглавие : 4-dimensional theory of K0-meson decay
Разночтения заглавия :авие SCOPUS: Four-dimensional theory of K0-meson decay
Место публикации : J. Phys. G. - 1987. - Vol. 13, Is. 11. - P.1343-1353. - ISSN 0954-3899, DOI 10.1088/0305-4616/13/11/008
Примечания : Cited References: 20
WOS,
Scopus
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Fedorov A. S., Eremkin E. V., Krasnov P. O., Gerasimov V. S., Agren H., Polyutov S. P.
Заглавие : A hybrid quantum–classical theory for predicting terahertz charge-transfer plasmons in metal nanoparticles on graphene
Колич.характеристики :13 с
Место публикации : J. Chem. Phys. - 2024. - Vol. 160, Is. 4. - Ст.044117. - ISSN 00219606 (ISSN), DOI 10.1063/5.0178247. - ISSN 10897690 (eISSN)
Примечания : Cited References: 61. - This study was funded by the Ministry of Science and High Education of Russian Federation, Project No. FSRZ-2023-0006. The calculations of CTPs in specific NP–graphene complexes were performed within the RSF Grant No. 23-12-20007 and the Krasnoyarsk Territorial Foundation for Support of Scientific and R & D Activities, Agreement No. 256. H. Ågren was supported by the Swedish Science Research Council on Contract No. 2022-03405
Аннотация: Metal nanoparticle (NP) complexes lying on a single-layer graphene surface are studied with a developed original hybrid quantum–classical theory using the Finite Element Method (FEM) that is computationally cheap. Our theory is based on the motivated assumption that the carrier charge density in the doped graphene does not vary significantly during the plasmon oscillations. Charge transfer plasmon (CTP) frequencies, eigenvectors, quality factors, energy loss in the NPs and in graphene, and the absorption power are aspects that are theoretically studied and numerically calculated. It is shown the CTP frequencies reside in the terahertz range and can be represented as a product of two factors: the Fermi level of graphene and the geometry of the NP complex. The energy losses in the NPs are predicted to be inversely dependent on the radius R of the nanoparticle, while the loss in graphene is proportional to R and the interparticle distance. The CTP quality factors are predicted to be in the range ~ 10 – 100. The absorption power under CTP excitation is proportional to the scalar product of the CTP dipole moment and the external electromagnetic field. The developed theory makes it possible to simulate different properties of CTPs 3–4 orders of magnitude faster compared to the original FEM or the finite-difference time domain method, providing possibilities for predicting the plasmonic properties of very large systems for different applications.
Смотреть статью,
Читать в сети ИФ
Найти похожие

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 сборника (однотомник)
Шифр издания :
Автор(ы) : Komarov S. A., Scherbinin V. V.
Заглавие : A Surface Wave Excitation by a Finite Phased Plane Waveguide Array with an Impedance Flange
Место публикации : 12th International Conference on Mathematical Methods in Electromagnetic Theory, 2008, Odesa, Ukraine, 2008. pp. 314-316
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Mikhaleva N. S., Visotin M. A., Popov Z. I., Kuzubov A. A., Fedorov A. S.
Заглавие : Ab initio and empirical modeling of lithium atoms penetration into silicon
Место публикации : Comput. Mater. Sci.: Elsevier, 2015. - Vol. 109. - P.76-83. - ISSN 0927-0256, DOI 10.1016/j.commatsci.2015.06.024
Примечания : Cited References: 69. - The authors would like to thank the Institute of Computational Modeling SB RAS, Krasnoyarsk, Information Technology Centre Novosibirsk State University, for providing access to their computational resources. The reported study was supported by RFBR, research project No. 14-02-31071, 14-02-31309, 12-02-00640, by the Council of the President of the Russian Federation for Support of Young Scientists and Leading Scientific Schools (project No. NSh-2886.2014.2), Increase Competitiveness Program of NUST "MISiS" (No. K2-2015-033). The authors also would like to thank Prof. Stephan Irle and L.R. Moskvina for fruitful discussions and helpful ideas.
Предметные рубрики: LONG CYCLE LIFE
CORE-LEVEL SPECTROSCOPY
CARBON-COATED SILICON
AUGMENTED-WAVE METHOD
ION BATTERIES
MOLECULAR-DYNAMICS
INTERATOMIC POTENTIALS
ELECTRONIC-STRUCTURE
CRYSTALLINE SILICON
SI(100)2X1 SURFACE
Ключевые слова (''Своб.индексиров.''): li-ion batteries--silicon--surface diffusion--li diffusion--density functional theory--molecular dynamics
Аннотация: A process of lithium atoms penetration into silicon (1 0 0) subsurface layers was investigated with the help of DFT method. It was shown that, while the concentration of lithium adatoms on reconstructed (1 0 0) silicon surface is low, the bonding energy of lithium atoms in the subsurface layers is smaller than the bonding energy on the surface, so lithium atoms are unlikely to migrate into the crystal. When the (1 0 0) silicon surface is covered by 2 layers of lithium, migration into the subsurface layer becomes favorable. In addition to this, the reconstruction of the surface changes to the form with symmetric dimers as the concentration increases. Thus, all possible lithium migration paths become energy-wise equal, so the rate of lithium atom transfer into silicon crystal rises. In addition to the ab initio calculations, an ad-hoc empirical interatomic potential was developed and the kinetics of lithium diffusion into silicon were studied. It was shown that lithium penetration proceeds in a layer-by-layer way with a sharp border between undoped and lithiated silicon. This is accounted for the fact that, once a tetrahedral interstice is occupied by a lithium atom, the migration barriers between the adjacent interstices become lower and the rate of diffusion increases. © 2015 Elsevier B.V. All rights reserved.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zinenko V. I., Zamkova N. G.
Заглавие : Ab initio calculation of the ferroelectric phase transition in disordered and ordered PbSc0.5Ta0.5O3 and PbSc0.5Nd0.5O3 solid solutions with the use of a model Hamiltonian
Разночтения заглавия :авие SCOPUS: Ab initio calculation of the ferroelectric phase transition in disordered and ordered PbSc0.5Ta0.5O3 and PbSc 0.5Nd0.5O3 solid solutions with the use of a model Hamiltonian
Место публикации : J. Exp. Theor. Phys.: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2008. - Vol. 106, Is. 3. - P542-549. - ISSN 1063-7761, DOI 10.1134/S1063776108030138
Примечания : Cited References: 17
Предметные рубрики: RELAXOR FERROELECTRICS
PEROVSKITES
BATIO3
PBTIO3
Ключевые слова (''Своб.индексиров.''): approximation theory--ferroelectric materials--hamiltonians--mathematical models--monte carlo methods--phase transitions--ferroelectric phase transition--gordon-kim model--local-mode approximation--solid solutions
Аннотация: To describe the ferroelectric phase transition in ordered and disordered PbSc0.5Ta0.5O3 (PST) and PbSc0.5Nd0.5O3 (PSN) solid solutions, a model Hamiltonian is written in the local-mode approximation, in which long-range dipole-dipole and short-range interactions of local modes are taken into account. The Hamiltonian parameters are determined from the set of energies of a series of distorted structures, calculated within the nonempirical generalized Gordon-Kim model. The statistical mechanics of the systems with a model Hamiltonian is investigated by the Monte Carlo method. It is revealed that PSN solid solutions undergo a transition to the ferroelectric rhombohedral phase through an intermediate phase, existing in a narrow temperature range. PST solid solutions undergo a ferroelectric phase transition directly from the paraelectric cubic to the ferroelectric rhombohedral phase.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Maksimov E. G., Zinenko V. I., Zamkova N. G.
Заглавие : Ab initio calculations of the physical properties of ionic crystals
Место публикации : Phys. Usp.: TURPION LTD, 2004. - Vol. 47, Is. 11. - P1075-1099. - ISSN 1063-7869, DOI 10.1070/PU2004v047n11ABEH001796
Примечания : Cited References: 90
Предметные рубрики: STRUCTURAL PHASE-TRANSITION
LOCAL-FIELD CORRECTIONS
INDUCED BREATHING MODEL
ZINC-BLENDE STRUCTURE
ELECTRON-GAS THEORY
LATTICE-DYNAMICS
MICROSCOPIC CALCULATIONS
MACROSCOPIC POLARIZATION
STATISTICAL-MECHANICS
1ST-PRINCIPLES THEORY
Аннотация: First-principles calculations of the physical properties of ionic crystals are reviewed. Two markedly different approaches within the framework of the density functional theory are described. In one of them, the electron spectrum and wave functions are treated within the standard band picture based on the solution of Kohn-Sham equations. In the second approach, the total electron density of a crystal is represented as a super-position of the densities of individual ions. The problem of determining the electric polarization of a crystal is discussed for each approach. It is shown that it is the use of Bloch functions rather than the physics of the phenomenon that complicates the solution of this problem within the Kohn-Sham framework. The deformable and polarizable ion model is described in detail, and its application to calculating many properties of ionic crystals, including the lattice dynamics and structural stability of crystal phases, is discussed.
WOS,
Scopus
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kuzubov A. A., Tikhonova L. V., Fedorov A. S.
Заглавие : Ab initio investigation of a new boron nitride allotrope
Коллективы : Russian Foundation for Basic Research [12-02-00640]
Место публикации : Phys. Status Solidi B. - 2014. - Vol. 251, Is. 6. - P.1282-1285. - ISSN 0370-1972, DOI 10.1002/pssb.201350389. - ISSN 1521-3951
Примечания : Cited References: 31. - We acknowledge support of the Russian Foundation for Basic Research through Grant No. 12-02-00640. Also, we thank the Institute of Computer Modeling (Siberian Division, Russian Academy of Sciences, Krasnoyarsk), the Joint Supercomputer Center of the Russian Academy of Sciences (Moscow), the computer cluster "Chebyshev" of the Moscow State University (Moscow), and the supercomputer of the Institute of Space and Information Technologies of the Siberian Federal University for providing an opportunity to use their computers for performing all calculations.
Предметные рубрики: AUGMENTED-WAVE METHOD
MOLECULAR-DYNAMICS
TRANSITION
METALS
Ключевые слова (''Своб.индексиров.''): boron nitride--computational materials science--density functional theory--elastic properties--superhard materials
Аннотация: A new allotropic superhard and superdense structure of sp3-bonded boron nitride (hP3-BN) is proposed. Geometric electronic, elastic, and optical properties of the structure are investigated by density functional theory generalized gradient approximation (DFT-GGA) calculations. It is shown that the structure is an insulator with a band gap of 5.06 eV; is density is 5.03% higher than that of cubic boron nitride (c-BN) and its bulk modulus is 2.25% higher than that of c BN. The calculated hP3-BN refractive index in the range 200-800 nm is significantly higher than the indexes of diamond and all known carbon allotropes, expect for the analogous carbon h-P3 structure, and it has a large optical dispersion. In the range above 800 nm the refractive index changes from 2.60 to 2.35. (C) WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Nemtsev A. V., Zhandun V. S., Zinenko V. I.
Заглавие : Ab initio study of the polarization, electronic, magnetic, and optical properties of perovskite SrMO3 (M = Fe, Mn) crystals and thin films containing magnetic ions
Место публикации : J. Exp. Theor. Phys. - 2018. - Vol. 126, Is. 4. - P.497-505. - ISSN 10637761 (ISSN), DOI 10.1134/S1063776118030056
Примечания : Cited References: 30
Ключевые слова (''Своб.индексиров.''): antiferromagnetism--density functional theory--electronic properties--iron compounds--manganese compounds--optical properties--perovskite--perovskite solar cells--polarization--strontium compounds
Аннотация: The magnetic, electronic, and polarization properties of the SrFeO3 and SrMnO3 compounds with a perovskite structure are calculated using the density functional theory in the bulk and thin-film states. A ferroelectric instability is found to be absent in the bulk state, and the polar mode is softened in the thin-film state of SrMnO3 in the presence of tensile stresses in the substrate. As a result, a polar phase with a polarization of 23 μC/cm2 appears, which agrees with experimental data. The study of the magnetic and electronic properties demonstrates the existence of G-type antiferromagnetic ordering in SrMnO3 and the appearance of a dielectric gap of about 1.5 eV in its thin film. A ferromagnetic phase with metallic conduction in both the bulk and thin-film states is detected in SrFeO3.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bulgakov E. N., Pichugin K. N., Sadreev A. F.
Заглавие : All-optical light storage in bound states in the continuum and release by demand
Коллективы : Russian Scientific Foundation [14-12-00266]
Место публикации : Opt. Express: Optical Society of America, 2015. - Vol. 23, Is. 17. - P.22520-22531. - ISSN 1094-4087, DOI 10.1364/OE.23.022520
Примечания : Cited References: 45. - This work was supported by Russian Scientific Foundation through Grant 14-12-00266. We acknowledge discussions with D.N. Maksimov
Предметные рубрики: TRAPPED RAINBOW STORAGE
COUPLED-MODE THEORY
CRYSTAL WAVE-GUIDE
SLOW LIGHT
FANO RESONANCE
METAMATERIALS
MICROCAVITY
CAVITIES
Аннотация: In the framework of the temporal coupled mode theory we consider bound states embedded in the continuum (BSC) of photonic crystal waveguide as a capacity for light storage. A symmetry protected BSC occurs in two off-channel microresonators positioned symmetrically relative to the waveguide. We demonstrate that the symmetry protected BSC captures a fraction of a light pulse due to the Kerr effect as the pulse passes by the microresonators. However the amount of captured light is found to be strongly sensitive to the parameters of the gaussian light pulse such as basic frequency, duration and intensity. In contrast to the above case the BSC resulted from a full destructive interference of two eigenmodes of a single microresonator accumulates a fixed amount of light dependent on the material parameters of the microresonator but independent of the light pulse. The BSCs in the Fabry-Perot resonator show similar effects. We also show that the accumulated light can be released by a secondary pulse. These phenomena pave a way for all-optical storage and release of light. (C) 2015 Optical Society of America
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Fedorov D.G., Kitaura K., Avramov P. V., Jensen J.H.
Заглавие : Analytic gradient for the adaptive frozen orbital bond detachment in the fragment molecular orbital method
Место публикации : Chem. Phys. Lett. - 2009. - Vol. 477, Is. 1-3. - P.169-175. - JUL 28. - ISSN 0009-2614, DOI 10.1016/j.cplett.2009.06.072
Примечания : Cited Reference Count: 49. - Гранты: We thank Professor M. Suenaga of Kyushu University for continuing his development of the modeling software FACIO and its FMO interface. D. G. F. and K. K. were supported by the a Grant-in- Aid for Scientific Research (JSPS, Japan) and the Next Generation SuperComputing Project, Nanoscience Program (MEXT, Japan). J.H.J. was supported by a Skou Fellowship from the Danish Research Agency (Forskningsradet for Natur og Univers).Финансирующая организация: JSPS, Japan; Next Generation SuperComputing Project; MEXT, Japan; Danish Research Agency
Предметные рубрики: DENSITY-FUNCTIONAL THEORY
GEOMETRY OPTIMIZATIONS
SEMICONDUCTOR NANOWIRES
SILICON NANOWIRES
METHOD FMO
ENERGY
SURFACES
RECONSTRUCTION
CHEMISTRY
PROTEINS
Ключевые слова (''Своб.индексиров.''): energy gradients--fragment molecular orbital methods--future applications--geometry optimization--numerical criteria--silicon nanowires--molecular modeling--molecular orbitals
Аннотация: We have developed and implemented the analytic energy gradient for the bond detachment scheme in the fragment molecular orbital method (FMO) suitable to describe solids, and applied it to the geometry optimization of a silicon nanowire at several levels of theory. In addition, we have examined in detail the effects of the particular choice of the fragmentation upon the accuracy and introduced a number of numerical criteria to characterize the errors. The established route is expected to provide guidance for future applications of FMO to surfaces, solids and nanosystems. (C) 2009 Elsevier B. V. All rights reserved.
WOS,
Scopus,
eLibrary
Найти похожие

12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Val'kov V. V., Zlotnikov A. O.
Заглавие : Anomalies in the characteristics of electronic structure upon a quantum phase transition to a state with two order parameters and the breaking of time-reversal symmetry
Место публикации : Bull. Russ. Acad. Sci. Phys.: Allerton Press, 2016. - Vol. 80, Is. 6. - P.616-619. - ISSN 10628738 (ISSN), DOI 10.3103/S106287381606040X
Примечания : Cited References: 9
Ключевые слова (''Своб.индексиров.''): antiferromagnetism--electronic structure--phase transitions--temperature distribution--antiferromagnetic order parameter--density of state--landau expansion--periodic anderson model--quantum phase transitions--temperature dependence--time reversal symmetries--two order parameters--quantum theory
Аннотация: Based on the periodic Anderson model, microscopic expressions for the Ginzburg–Landau expansion coefficients in a phase with superconducting and antiferromagnetic order parameters are obtained. Temperature dependences of the order parameters near the temperature of the transition to this phase are established. The emergence of anomalous properties upon the quantum phase transition to the phase with two order parameters is investigated. This transition is accompanied by drastic reconstruction of the density of states, reflected by the interplay between superconductivity and antiferromagnetism. © 2016, Allerton Press, Inc.
Смотреть статью,
Scopus,
Читать в сети ИФ
Найти похожие

13.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Kuz'min V. I., Nikolaev S. V., Ovchinnikov S. G.
Заглавие : Anomalous spectral properties of strongly correlated systems within the cluster perturbation theory
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. 2. - Ст.I.P9. - P.151-152. - ISBN 978-5-9500855-7-4 (Шифр В33/E12-125657784)
Примечания : Cited References: 4. - The reported study was funded by Russian Foundation for Basic Research (RFBR) according to the research project no. 18-32-00256, RFBR and Government of Krasnoyarsk Territory, Krasnoyarsk Regional Fund of Science to the research project: “18-42-240017 Features of electron-phonon coupling in high-temperature superconductors with strong electron correlations” and the research project: “18-42-243004 New thermoelectric materials based on multi-scale spatially inhomogeneous substituted rare-earth cobalt oxides and the Ruddlesden-Popper phases”
Материалы симпозиума,
Читать в сети ИФ
Найти похожие

14.

15.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : SANDALOV I. S., YUSHKOVA E. Y.
Заглавие : ANTI-FERROMAGNETIC TRANSITION THEORY IN URANIUM MONOPNICTIDES
Место публикации : Fiz. Tverd. Tela: MEZHDUNARODNAYA KNIGA, 1983. - Vol. 25, Is. 11. - P3437-3439. - ISSN 0367-3294
Примечания : Cited References: 4
WOS
Найти похожие

16.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Petrov M. I., Balaev D. A., Gokhfeld D. M., Ospishchev S. V., Shaikhutdinov K. A., Aleksandrov K. S.
Заглавие : Applicability of the theory based on Andreev reflection to the description of experimental current-voltage characteristics of polycrystalline HTSC plus normal metal composites
Место публикации : Physica C. - 1999. - Vol. 314, Is. 1-2. - P.51-54. - ISSN 0921-4534, DOI 10.1016/S0921-4534(99)00151-3
Примечания : Cited References: 19
Предметные рубрики: WEAK LINKS
JUNCTIONS
FILMS
Ключевые слова (''Своб.индексиров.''): ybacuo + bapbo3 composites--network of weak s-n-s links--current-voltage characteristic
Аннотация: Measurements of current-voltage characteristics (CVC) of Y3/4Lu1/4Ba2,Cu3O7 + BaPbO3 and Y3/4Lu1/4Ba2Cu3O7 +BaPb0.9Sn0.1O3 composites modelling network of superconducting-normal metal-superconducting (S-N-S) junctions in effectively 'clean' and 'dirty' limits, respectively, have been performed. Essential difference of CVCs for these composites is observed in spite of the identical preparation technique and experimental conditions. It is shown that the theory for S-N-S junctions [R. Kummel, U. Gunsenheimer, R. Nicolsky, Phys. Rev. B, 42 (1990) 3932] well describes the experimental CVCs of the composites in both cases. (C) 1999 Published by Elsevier Science B.V. All rights reserved.
WOS,
Читать в сети ИФ
Найти похожие

17.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Sorokin P. B., Ovchinnikov S. G., Avramov P. V., Chernozatonskii L.A., Fedorov D.G.
Заглавие : Atypical quantum confinement effect in silicon nanowires
Место публикации : J. Phys. Chem. A. - WASHINGTON: AMER CHEMICAL SOC, 2008. - Vol. 112, Is. 40. - С. 9955-9964. - OCT 9. - ISSN 1089-5639, DOI 10.1021/jp805069b
Примечания : Cited Reference Count: 25. - Гранты: This work was in part partially supported by a CREST (Core Research for Evolutional Science and Technology) grant in the Area of High Performance Computing for Multiscale and Multiphysics Phenomena from the Japan Science and Technology Agency (JST) as well as by Russian Fund of Basic Researches (grant 08-02-01096) (L.A.C.). P.V.A. acknowledges the encouragement of Dr. Keiji Morokuma, Research Leader at Fukui Institute for Fundamental Chemistry. The geometry of all presented structures was visualized by ChemCraft software.SUP25/SUP L.A.C. acknowledges I. V. Stankevich for help and fruitful discussions. P.B.S. is grateful to the Joint Supercomputer Center of the Russian Academy of Sciences for access to a cluster computer for quantum-chemical calculations.Финансирующая организация: Japan Science and Technology Agency (JST); Russian Fund of Basic Researches [08-02-01096]
Предметные рубрики: ELECTRONIC-STRUCTURE
OPTICAL-PROPERTIES
SI
DENSITY
WIRES
EXCHANGE
ATOMS
DOTS
Ключевые слова (''Своб.индексиров.''): electric wire--energy gap--gallium alloys--mathematical models--nanostructured materials--nanostructures--nanowires--quantum confinement--quantum electronics--semiconductor quantum dots--silicon--ami methods--band gaps--blue shifts--dinger equations--linear junctions--monotonic decreases--quantum confinement effects--quantum dots--semiempirical--silicon nanowires--system sizes--theoretical models--nanocrystalline silicon--nanowire--quantum dot--silicon--article--chemistry--electron--quantum theory--electrons--nanowires--quantum dots--quantum theory--silicon
Аннотация: The quantum confinement effect (QCE) of linear junctions of silicon icosahedral quantum dots (IQD) and pentagonal nanowires (PNW) was studied using DFT and semiempirical AM1 methods. The formation of complex IQD/PNW structures leads to the localization of the HOMO and LUMO on different parts of the system and to a pronounced blue shift of the band gap; the typical QCE with a monotonic decrease of the band gap upon the system size breaks down. A simple one-electron one-dimensional Schrodinger equation model is proposed for the description and explanation of the unconventional quantum confinement behavior of silicon IQD/PNW systems. On the basis of the theoretical models, the experimentally discovered deviations from the typical QCE for nanocrystalline silicon are explained.
WOS,
Scopus,
eLibrary
Найти похожие

18.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Rotter I., Sadreev A. F.
Заглавие : Avoided level crossings, diabolic points, and branch points in the complex plane in an open double quantum dot
Место публикации : Phys. Rev. E: AMERICAN PHYSICAL SOC, 2005. - Vol. 71, Is. 3. - Ст.36227. - ISSN 1063-651X, DOI 10.1103/PhysRevE.71.036227
Примечания : Cited References: 49
Предметные рубрики: BERRY TOPOLOGICAL PHASE
EXCEPTIONAL POINTS
GEOMETRIC PHASES
NUCLEAR REACTIONS
RESONANCE STATES
UNIFIED THEORY
S-MATRIX
CONTINUUM
REPULSION
INTERFEROMETER
Ключевые слова (''Своб.индексиров.''): branch points in the complex plane (bpcp)--diabolic points (dp)--geometric phases--riemann sheets--eigenvalues and eigenfunctions--electron energy levels--functions--hamiltonians--quantum theory--resonance--topology--semiconductor quantum dots
Аннотация: We study the spectrum of an open double quantum dot as a function of different system parameters in order to receive information on the geometric phases of branch points in the complex plane (BPCP). We relate them to the geometrical phases of the diabolic points (DPs) of the corresponding closed system. The double dot consists of two single dots and a wire connecting them. The two dots and the wire are represented by only a single state each. The spectroscopic values follow from the eigenvalues and eigenfunctions of the Hamiltonian describing the double dot system. They are real when the system is closed, and complex when the system is opened by attaching leads to it. The discrete states as well as the narrow resonance states avoid crossing. The DPs are points within the avoided level crossing scenario of discrete states. At the BPCP, width bifurcation occurs. Here, different Riemann sheets evolve and the levels do not cross anymore. The BPCP are physically meaningful. The DPs are unfolded into two BPCP with different chirality when the system is opened. The geometric phase that arises by encircling the DP in the real plane, is different from the phase that appears by encircling the BPCP. This is found to be true even for a weakly opened system and the two BPCP into which the DP is unfolded.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

19.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Avramov P. V., Sorokin P. B., Fedorov A. S., Fedorov D. G., Maeda Y.
Заглавие : Band-gap unification of partially Si-substituted single-wall carbon nanotubes
Место публикации : Phys. Rev. B: AMER PHYSICAL SOC, 2006. - Vol. 74, Is. 24. - Ст.245417. - ISSN 1098-0121, DOI 10.1103/PhysRevB.74.245417
Примечания : Cited References: 72
Предметные рубрики: SILICON-CARBIDE NANOTUBES
DENSITY-FUNCTIONAL THEORY
TOTAL-ENERGY CALCULATIONS
WAVE BASIS-SET
ELECTRONIC-STRUCTURE
AB-INITIO
NANORODS
EXCITATIONS
TRANSITION
NANOWIRES
Аннотация: The atomic and electronic structure of a set of pristine single wall SiC nanotubes as well as Si-substituted carbon nanotubes and a SiC sheet was studied by the local-density approximation (LDA) plane wave band structure calculations. Consecutive substitution of carbon atoms by Si leads to a gap opening in the energetic spectrum of the metallic (8,8) SWCNT with approximately quadratic dependence of the band gap upon the Si concentration. The same substitution for the semiconductor (10,0) single wall carbon nanotubes (SWCNT) results in a band gap minimum (0.27 eV) at similar to 25% of Si concentration. In the Si concentration region of 12-18 %, both types of nanotubes have less than 0.5 eV direct band gaps at the Gamma-Gamma point. The calculation of the chiral (8,2) SWSi0.15C0.85NT system gives a similar (0.6 eV) direct band gap. The regular distribution of Si atoms in the atomic lattice is by similar to 0.1 eV/atom energetically preferable in comparison with a random distribution. Time dependent density functional theory (DFT) calculations showed that the silicon substitution sufficiently increases (roughly by one order of magnitude) the total probability of optical transitions in the near infrared region, which is caused by the opening of the direct band gap in metallic SWCNTs, the unification of the nature and energy of the band gaps of all SWCNT species, the large values of Si3p parallel to r parallel to Si3s radial integrals and participation of Si3d states in chemical bonding in both valence and conductance bands.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

20.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Shneyder E., Ovchinnikov S.
Заглавие : BCS-type Theory for the Sum of Magnetic and Phonon Coupling in high-Tc Cuprates
Коллективы : International Conference on Magnetism
Место публикации : 18th International Conference on Magnetism (ICM-2009). - 2009. - Ст.Mo-A-5.1-03
Найти похожие