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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) : Atuchin V. V., Isaenko L. I., Kesler V. G., Lin Z. S., Molokeev M. S., Yelisseyev A. P., Zhurkov S. A.
Заглавие : Exploration on anion ordering, optical properties and electronic structure in K3WO3F3 elpasolite
Место публикации : J. Solid State Chem. - 2012. - Vol. 187. - P.159-164. - ISSN 0022-4596, DOI 10.1016/j.jssc.2011.12.037
Примечания : Cited References: 50. - This study is partly supported by SB RAS Project No. 34. ZSL acknowledges the funding support of No. 91022036, 11174297, 2010CB630701, and 2011CB922204 in China. Authors also wish to thank V. D. Fokina for microcaloric measurements.
Предметные рубрики: PHASE-TRANSITIONS
CRYSTAL-GROWTH
FERROELECTRIC K3WO3F3
SOLID-STATE
OXYFLUORIDE
FLUORIDE
POLAR
CS
(NH4)(3)MOO3F3
APPROXIMATION
Anion ordering
Chemical routes
Elpasolite
First-priciples calculation
Forbidden band
Low temperatures
Non-linear optical coefficients
Nonlinear optical crystal
Optical transparency
Oxyfluorotungstate
Room temperature
Ключевые слова (''Своб.индексиров.''): oxyfluorotungstate--structure--nonlinear optical crystals--electronic and optical properties--first-principles calculations
Аннотация: Room-temperature modification of potassium oxyfluorotungstate, G(2)-K3WO3F3, has been prepared by low-temperature chemical route and single crystal growth. Wide optical transparency range of 0.3-9.4 mu m and forbidden band gap E-g=4.32 eV have been obtained for G(2)-K3WO3F3 crystal. Meanwhile, its electronic structure has been calculated with the first-principles calculations. The good agreement between the theorectical and experimental results have been achieved. Furthermore, G(2)-K3WO3F3 is predicted to possess the relatively large nonlinear optical coefficients. (C) 2012 Elsevier Inc. All rights reserved.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Avramov P. V., Kuzubov A. A., Sakai, Seiji, Ohtomo, Manabu, Entani, Shiro, Matsumoto, Yoshihiro, Naramoto, Hiroshi, Eleseeva N. S.
Заглавие : Contact-induced spin polarization in graphene/h-BN/Ni nanocomposites
Место публикации : J. Appl. Phys.: American Institute of Physics, 2012. - Vol. 112, Is. 11. - Ст.114303. - P. - ISSN 0021-8979, DOI 10.1063/1.4767134
Примечания : Cited References: 47. - 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. The authors are grateful to the ICS SB RAS and SFU CC (Krasnoyarsk), ISC RAS and MSU CRC, (SKIF MSU "Chebyshev", Moscow) for computer resources. This work was partially supported by the RFBR grant 12-02-31417.
Предметные рубрики: HEXAGONAL BORON-NITRIDE
TRILAYER GRAPHENE
NI(111) SURFACE
GRAPHITE
APPROXIMATION
SPINTRONICS
DIFFRACTION
SIMULATION
SUBSTRATE
CARBON
Аннотация: Atomic and electronic structure of graphene/Ni(111), h-BN/Ni(111) and graphene/h-BN/Ni(111) nanocomposites with different numbers of graphene and h-BN layers and in different mutual arrangements of graphene/Ni and h-BN/Ni at the interfaces was studied using LDA/PBC/PW technique. Using the same technique corresponding graphene, h-BN and graphene/h-BN structures without the Ni plate were calculated for the sake of comparison. It was suggested that C-top:C-fcc and N-top:B-fcc configurations are energetically favorable for the graphene/Ni and h-BN/Ni interfaces, respectively. The Ni plate was found to induce a significant degree of spin polarization in graphene and h-BN through exchange interactions of the electronic states located on different fragments. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4767134]
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Loiko V. A., Zyryanov V. Ya., Konkolovich A. V., Misckevich A. A., Krakhalev M. N., Maschke U.
Заглавие : Investigation of transmittance and small-angle light scattering by monolayer of liquid crystal droplets with modified boundary conditions
Коллективы : International Topical Meeting: Optics of Liquid Crystals (14th; Sept 25 - Oct 1, 2011; Yerevan, Armenia)
Место публикации : Mol. Cryst. Liquid Cryst. - 2012. - Vol. 561, Is. 1. - P.194-202. - ISSN 1542-1406, DOI 10.1080/15421406.2012.687237
Примечания : Cited References: 24
Предметные рубрики: NEMATIC DROPLETS
ANOMALOUS DIFFRACTION
APPROXIMATION
FILM
Ключевые слова (''Своб.индексиров.''): light modulation--light scattering--polymer dispersed liquid crystal--optical transmittance
Аннотация: A numerical method for modelling transmittance and angular distribution of light scattered by a Polymer Dispersed Liquid Crystal (PDLC) film, containing droplets with inhomogeneous boundary conditions, is proposed. It is based on the anomalous diffraction approximation and an interference approximation. The internal structures of nematic LC droplets are calculated on the basis of the free energy minimization problem solution using the relaxation method. The results for a monolayer of spherical LC droplets with modified boundary conditions caused by the local increase of the concentration of surface-active ions at the polymer-LC interface are discussed.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Korshunov M. M., Eremin I., Shorikov A., Anisimov V. I., Renner M., Brenig W.
Заглавие : Itinerant in-plane magnetic fluctuations and many-body correlations in NaxCoO2
Разночтения заглавия :авие SCOPUS: Itinerant in-plane magnetic fluctuations and many-body correlations in Nax Co O2
Место публикации : Phys. Rev. B: AMERICAN PHYSICAL SOC, 2007. - Vol. 75, Is. 9. - Ст.94511. - ISSN 1098-0121, DOI 10.1103/PhysRevB.75.094511
Примечания : Cited References: 47
Предметные рубрики: TRANSITION-METALS
WAVE-FUNCTIONS
HUBBARD-MODEL
FERMI-SURFACE
ENERGY-BANDS
FERROMAGNETISM
APPROXIMATION
DIMENSIONS
SYSTEMS
FIELD
Аннотация: Based on the ab initio band structure for NaxCoO2, we derive the single-electron energies and the effective tight-binding description for the t(2g) bands using projection procedure. Due to the presence of the next-nearest-neighbor hoppings, a local minimum in the electronic dispersion close to the Gamma point of the first Brillouin zone forms. Correspondingly, in addition to a large Fermi surface, an electron pocket close to the Gamma point emerges at high doping concentrations. The latter yields a scattering channel, resulting in a peak structure of the itinerant magnetic susceptibility at small momenta. This indicates dominant itinerant in-plane ferromagnetic fluctuations above a certain critical concentration x(m), in agreement with neutron scattering data. Below x(m), the magnetic susceptibility shows a tendency toward the antiferromagnetic fluctuations. We further analyze the many-body effects on the electronic and magnetic excitations using various approximations applicable for different U/t ratios.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zobov V. E., Popov M. A.
Заглавие : The coordinate of the singular point of generating functions of clusters in the high-temperature dynamics of spin lattice systems with axially symmetric interaction
Место публикации : Theor. Math. Phys.: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2003. - Vol. 136, Is. 3. - P1297-1311. - ISSN 0040-5779, DOI 10.1023/A:1025603416535
Примечания : Cited References: 25
Предметные рубрики: CONSISTENT FLUCTUATING FIELD
NUCLEAR-DOUBLE-RESONANCE
HEISENBERG PARAMAGNET
LINE SHAPE
RELAXATION
SPECTRUM
APPROXIMATION
CRYSTALS
MOMENT
CAF2
Ключевые слова (''Своб.индексиров.''): spin dynamics--singular points--expansion over the reciprocal space dimension--expansion over the reciprocal space dimension--singular points--spin dynamics
Аннотация: We investigate generating functions for equipped trees composed of double bonds of two sorts on a hypercubic lattice of dimension d with built-in fragments. Rules for constructing these clusters are chosen to ensure the estimate for coefficients of power series in time for the longitudinal and transverse autocorrelation functions of the spin system with axially symmetric interaction. We derive a system of two equations for the tree-generating functions and an equation for the generating functions of chains leading from the root to a fragment in a tree using the Bethe approximation and under the condition that mainly bonds of one sort are taken into account. For the face-centered hypercubic lattice, we find the First terms of the 1/d expansion for the coordinate of the singular point of the generating function in both the anisotropic and the isotropic cases taking fragments in the forms of a triangle from four bonds and a four-fold bound pair into account. The obtained result is written in terms of ratios of lattice sums and is generalized to nuclear spin systems with dipole-dipole interaction. The theoretical value of the singular-point coordinate agrees well with the experimental value calculated from the tail of the absorption spectrum of the nuclear magnetic resonance in a barium fluoride monocrystal.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Di Valentin C., Neyman K. M., Risse T., Sterrer M., Fischbach E., Freund H. J., Nasluzov V. A., Pacchioni G., Rosch N.
Заглавие : Density-functional model cluster studies of EPR g tensors of F-s(+) centers on the surface of MgO
Разночтения заглавия :авие SCOPUS: Density-functional model cluster studies of EPR g tensors of F s + centers on the surface of MgO
Место публикации : J. Chem. Phys.: AMER INST PHYSICS, 2006. - Vol. 124, Is. 4. - Ст.44708. - ISSN 0021-9606, DOI 10.1063/1.2161190
Примечания : Cited References: 37
Предметные рубрики: ELECTRONIC G-TENSORS
CORRELATION-ENERGY
MGO(001) SURFACE
OXYGEN VACANCIES
SPIN-ORBIT
G-VALUES
ATOMS
APPROXIMATION
COMPLEXES
MOLECULES
Ключевые слова (''Своб.индексиров.''): density-functional model cluster--single-crystalline thin films--spin-orbit interaction--anisotropy--paramagnetic resonance--single crystals--tensors--thin films--magnesium compounds
Аннотация: We report g tensors of surface color centers, so-called F-s(+) centers, of MgO calculated with two density-functional approaches using accurately embedded cluster models. In line with recent UHV measurements on single-crystalline MgO film, we determined only small g-tensor anisotropies and negative shifts Delta g equivalent to g-g(e) for all F-s(+) sites considered, namely, (001)-terrace, step, edge, and corner sites. The g values are very sensitive to the local structure of the defect: relaxation reverses the sign of Delta g. However, accounting for the spin-orbit interaction either self-consistently or perturbatively yields very similar results. In addition to the values of the tensor components, their direction with respect to the surface was determined. In contrast to edges, significant deviations from ideal C-2v symmetry were found for F-s(+) centers at steps. Recent data on single-crystalline thin films are reevaluated in the light of these results. (c) 2006 American Institute of Physics.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Val'kov V. V., Zlotnikov A. O.
Заглавие : Manifestation of spin-charge fluctuations in the spectral and thermodynamic properties of quasi-two-dimensional rare-earth intermetallic compounds
Коллективы : RFBR [16-02-00073-a, 15-42-04372-r-Siberia-a]; Government of the Krasnoyarsk Region; Regional Science Foundation [07/16]; Integrated program II.2P of SB RAS [0358-2015-0002]; Presidential scholarships for young PhDs [SP-1370.2015.5]
Место публикации : Low Temp. Phys.: American Institute of Physics, 2017. - Vol. 43, Is. 2. - P.191-199. - ISSN 1063-777X, DOI 10.1063/1.4977211. - ISSN 1090-6517(eISSN)
Примечания : Cited References:35. - This work was supported by RFBR (Grants Nos. 16-02-00073-a and 15-42-04372-r-Siberia-a), the Government of the Krasnoyarsk Region and the Regional Science Foundation (Ext. Agreement No. 07/16), as well as the Integrated program II.2P of SB RAS (Project No. 0358-2015-0002). One of the authors (A.O.Z.) acknowledges the support by the Presidential scholarships for young PhDs (SP-1370.2015.5).
Предметные рубрики: PERIODIC ANDERSON MODEL
INTERMEDIATE-VALENCE COMPOUNDS
MAGNETIC PHASE-DIAGRAM
HEAVY
SUSCEPTIBILITY
APPROXIMATION
ANTIFERROMAGNETISM
SUPERCONDUCTIVITY
LATTICE
METALS
Аннотация: In the framework of the modified periodic Anderson model with exchange interaction in the subsystem of localized states, it is shown that spin-charge fluctuations in quasi-two-dimensional intermetallic compounds with rare-earth ions in the mixed valence state significantly affect both the spectrum of magnetic excitations and the conditions at which the antiferromagnetic phase is realized. The spectral characteristics of the phase were obtained by the method of the diagram technique for Hubbard operators in the one-loop approximation, which allows to account for the spincharge fluctuation contributions to the components of the mass and the force operators. The developed theory allowed to quantitatively describe the pressure dependence of the Neel temperature observed in a quasi-two-dimensional antiferromagnetic heavy-fermion intermetallic compound CeRhIn5. Published by AIP Publishing.
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