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Каталог книг и брошюр библиотеки ИФ СО РАН

Каталог журналов библиотеки ИФ СО РАН

Труды сотрудников ИФ СО РАН

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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Arkhipkin V. G., Gunyakov V. A., Myslivets S. A., Zyryanov V. Ya., Shabanov V. F.
Заглавие : Angular tuning of defect modes spectrum in the one-dimensional photonic crystal with liquid-crystal layer
Место публикации : Eur. Phys. J. E. - NEW YORK: SPRINGER, 2007. - Vol. 24, Is. 3. - С. 297-302. - NOV. - ISSN 1292-8941, DOI 10.1140/epje/i2007-10239-7
Примечания : Cited Reference Count: 28
Предметные рубрики: PERIODIC STRUCTURE
REFRACTIVE-INDEX
ENHANCEMENT
LIGHT
LASER
Ключевые слова (''Своб.индексиров.''): 42.25.bs wave propagation, transmission and absorption--42.70.df liquid crystals--42.70.qs photonic bandgap materials--angles of incidence--angular tuning--defect modes--electric polarization--photonic bandgap materials--radiation losses--absorption--defects--light polarization--liquid crystals--one dimensional--phase shift--wave propagation--photonic crystals
Аннотация: A one-dimensional ZrO2/SiO2 photonic crystal with a 4-n -pentyl-4'-cyanobiphenyl (5CB) nematic defect layer was used to investigate the transmission spectra of light polarized parallel and perpendicular to the liquid-crystal director at different angles of incidence. The spectra of the photonic crystal were shown to split into four polarized components T-ij at oblique incidence. When the incident angle increased, the bandgap edges and the defect modes shifted towards short wavelengths, while the amplitudes of the defect modes increased for the transverse magnetic polarization and decreased for the transverse electric polarization. The observed discrepancy between the defect mode amplitudes in the center and near the edges of the photonic bandgap was found to be related to the radiation losses inside the defect layer of a non-ideal photonic crystal. The simulated transmission spectra obtained using recurrence relations and taking into account the decay of defect modes are in good agreement with the experimental data.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Avramov P. V., Ovchinnikov S. G.
Заглавие : Underestimating the width of the bandgap in the electronic spectra of La2CuO4
Место публикации : Phys. Solid State: AMER INST PHYSICS, 1997. - Vol. 39, Is. 3. - P389-391. - ISSN 1063-7834, DOI 10.1134/1.1129865
Примечания : Cited References: 9
Предметные рубрики: SUPERCONDUCTIVITY
Аннотация: It is shown that the width of the bandgap determined by the simultaneous analysis of the experimental photoelectron and inverse photoemission spectra of the surface of La2CuO4 using a common energy scale is underestimated by 1 eV. The electronic and satellite structures of the spectra of La2CuO4 are calculated on the basis of the multiband p-d model and the sudden perturbation approximation. It is shown that shakedown processes shift the one-electron contour of the final two-hole configuration of the photoelectron spectrum 1 eV down the energy scale and shift the contour of the final d(10) configuration of the inverse photoemission spectrum downward by 2 eV; these shifts cause the energy splitting between the filled and empty bands to be underestimated. (C) 1997 American Institute of Physics.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Habibullayev N. N., Naumov N. G., Lavrov A.N., Kuratieva N. V., Aleksandrovsky A. S., Oreshonkov A. S., Molokeev M. S., Palamarchuk I. V., Yurev I. O., Denisenko Y. G., Andreev O. V., Zakharova A. D.
Заглавие : Magnetic, optical, and thermic properties of SrLnCuSe3 (Ln = Dy, Ho, Er, Tm) compounds
Место публикации : Magnetochemistry. - 2023. - Vol. 9, Is. 8. - Ст.194. - ISSN 23127481 (eISSN), DOI 10.3390/magnetochemistry9080194
Примечания : Cited References: 36. - The study was funded by the Russian Science Foundation, project No. 23-23-00488
Аннотация: SrLnCuSe3 (Ln = Dy, Ho, Er, Tm) compounds crystallize in the Pnma and Cmcm orthorhombic space group and belong to the Eu2CuS3 and KCuZrS3 structural type, respectively. According to a single-crystal XRD study, the SrTmCuSe3 unit cell parameters are a = 4.0631 (4), b = 13.4544 (14), c = 10.4430 (10) A, and V = 570.88 (10) A3. All the studied SrLnCuSe3 samples in the temperature range of 1.77–300 K demonstrate paramagnetic behavior without any features pointing to magnetic ordering. The measured Curie constants coincide with the values expected for Ln3+ ions with good accuracy, which confirms the stoichiometric composition of the samples and the non-magnetic state of the copper ions, Cu1+ (S = 0). The conducted optical absorption study showed that the polycrystalline SrLnCuSe3 (Ln = Dy, Ho, Er, Tm) samples are semiconductors with a direct bandgap ranging from 2.14 eV to 2.31 eV. Two indirect bandgaps were revealed and explained by the presence of optical transitions to highly dispersive subbands in the conduction band. The compounds demonstrate two reversible phase transitions α⇆β, β⇆γ and an incongruent melting at 1606 K (Dy), 1584 K (Ho), 1634 K (Er), and 1620 K (Tm) associated with the formation of solid solutions of SrSe, Cu2-XSe, and Ln2Se3 binary compounds.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Arkhipkin V. G., Gunyakov V. A., Myslivets S. A., Gerasimov V. P., Zyryanov V. Y., Vetrov S. Y., Shabanov V. F.
Заглавие : One-dimensional photonic crystals with a planar oriented nematic layer: Temperature and angular dependence of the spectra of defect modes
Место публикации : J. Exp. Theor. Phys.: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2008. - Vol. 106, Is. 2. - P388-398. - ISSN 1063-7761, DOI 10.1134/S1063776108020179
Примечания : Cited References: 58
Предметные рубрики: LIQUID-CRYSTAL
TRANSMISSION SPECTRUM
BANDGAP STRUCTURES
PERIODIC STRUCTURE
REFRACTIVE-INDEX
LATTICE-DEFECTS
LASER
ENHANCEMENT
SILICON
MICROCAVITIES
Аннотация: Transmission spectra of a one-dimensional photonic crystal (PC) formed by two multilayer dielectric mirrors and a planar oriented layer of 5CB nematic liquid crystal (LC) that is sandwiched between these mirrors and serves as a structure defect are investigated experimentally. Specific features of the behavior of the spectrum of defect modes as a function of the angle of incidence of light on the crystal are studied for two polarizations: parallel and perpendicular to the director of the LC; the director either lies in the plane of incidence or is perpendicular to it. It is shown that, for the configurations considered, the maxima of the defect modes shift toward the short-wavelength region as the tilt angle of incidence radiation increases; this tendency is more manifest for the parallel-polarized component, when the director lies in the plane of incidence. In the latter case, the width of the photonic band gap (PBG) appreciably decreases. The temperature dependence of the polarization components of the transmission spectra of a PC is investigated in the case of normal incidence of light. The spectral shift of defect modes due to the variation of the refractive index of the LC at the nematic-isotropic liquid phase transition point is measured. It is shown that, in real PCs, the amplitude of defect modes decreases when approaching the center of the band gap, as well as when the number of layers in the dielectric mirrors increases. Theoretical transmission spectra of the PCs calculated by the method of recurrence relations with regard to the decay of defect modes are in good agreement with experimental data.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shtarev D. S., Ryabchuk V. K., Rudakova A. V., Shtareva A. V., Molokeev M. S., Kirichenko E. A., Serpone N.
Заглавие : Phenomenological rule from correlations of conduction/valence band energies and bandgap energies in semiconductor photocatalysts: calcium bismuthates versus strontium bismuthates
Коллективы : Russian Science FoundationRussian Science Foundation (RSF) [19-73-10013]; Saint-Petersburg State University [39054581]
Место публикации : ChemCatChem. - 2020. - Vol. 12, Is. 6. - P.1551-1555. - ISSN 1867-3880, DOI 10.1002/cctc.201902236. - ISSN 1867-3899(eISSN)
Примечания : Cited References: 13. - The research was supported from a grant from the Russian Science Foundation (project No. 19-73-10013). We are very grateful to the staff of the Khabarovsk Innovation and Analytical Center of the Yu. A. Kosygin Institute of Tectonics and Geophysics FEB RAS, and of the Research Center on Nanophotonics and the Center for Physical Methods of Surface Investigation (to Dr. Alexandra Koroleva) of the Research Park at Saint-Petersburg State University for their valuable assistance in carrying out the research and in providing the needed equipment. VKR and AVR acknowledge financial support from a grant by the Saint-Petersburg State University (Pure ID 39054581). One of us (NS) thanks Prof. A. Albini and the staff of the PhotoGreen Laboratory of the University of Pavia for their continued hospitality
Предметные рубрики: STRUCTURAL-PROPERTIES
Аннотация: A number of calcium bismuthates were synthesized (25 to 50 mol% in Ca) and characterized by XRD, SEM, EDX, XPS and DRS techniques; the latter provided an estimate of the bandgap energies (Ebg=2.41 to 3.29 eV) via Tauc plots for indirect transitions, whereas XPS established the potentials (vs NHE) of their respective valence bands (and thus the conduction bands). Linear correlations existed between EVB/ECB and Ebg that when compared with those of strontium bismuthates (reported earlier) showed that differences in energies at Ebg=0 eV are related to the difference in the absolute electronegativities of Ca and Sr, from which the following empirical phenomenological rule is postulated: replacing one alkaline earth metal in bismuthates by another causes the points of intersection of the linear correlations ECB(Ebg) and EVB(Ebg) to be displaced by an amount equal to twice the difference in absolute electronegativities of these metals.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Huang K.-C., Hsiao Yu-Cheng, Timofeev I. V., Zyryanov V. Ya., Lee W.
Заглавие : Photo-manipulated photonic bandgap devices based on optically tristable chiral-tilted homeotropic nematic liquid crystal
Место публикации : Opt. Express: Optical Society of America, 2016. - Vol. 24, Is. 22. - P.25019-25025. - ISSN 10944087 (ISSN), DOI 10.1364/OE.24.025019
Примечания : Cited References: 22. - Ministry of Science and Technology (MOST), (103-2923-M-009-003-MY3); Ministry of Education and Science of the Russian Federation (3.1276.2014/K); Siberian Branch of the Russian Academy of Sciences under Complex Program II.2P (0358-2015-0010, 0358-2015-0011).
Ключевые слова (''Своб.индексиров.''): defects--energy gap--liquid crystals--nematic liquid crystals--photonic crystals--spontaneous emission--homeotropic nematic liquid crystals--intensity modulators--low-power consumption--multi-channel filter--one dimensional photonic crystal--photonic application--photonic bandgap devices--transmission characteristics--light transmission
Аннотация: We report on the spectral properties of an optically switchable tristable chiral-tilted homeotropic nematic liquid crystal (LC) incorporated as a tunable defect layer in one-dimensional photonic crystal. By varying the polarization angle of the incident light and modulating the light intensity ratio between UV and green light, various transmission characteristics of the composite were obtained. The hybrid structure realizes photo-tunability in transmission of defect-mode peaks within the photonic bandgap in addition to optical switchability among three distinct sets of defect modes via photoinduced tristable state transitions. Because the fabrication process is easier and less critical in terms of cell parameters or sample preparation conditions and the LC layer itself possesses an extra stable state compared with the previously reported bistable counterpart operating on the basis of biased-voltage dual-frequency switching, it has much superior potential for photonic applications such as a low-power-consumption multichannel filter and an optically controllable intensity modulator. © 2016 Optical Society of America.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Osseni S. А., Andreev P. O., Polkovnikov A. A., Zakharov B. A., Aleksandrovsky A. S., Abulkhaev M. U., Volkova S. S., Kamaev D. N., Kovenskiy I. M., Nesterova N. V., Kudomanov M. V., Andreev O. V.
Заглавие : Properties of oxysulfide phases and phase diagram of the Nd2S3–Nd2O3 system
Место публикации : J. Solid State Chem. - 2022. - Vol. 314. - Ст.123438. - ISSN 00224596 (ISSN), DOI 10.1016/j.jssc.2022.123438
Примечания : Cited References: 51. - This research was funded by the Tyumen Oblast Government , as part of the West-Siberian Interregional Science and Education Center's project No. 89-DON (3)
Аннотация: We have determined the thermal characteristics and optical properties of the sulfide and oxysulfide phases in the Nd2S3 - Nd2O3 system. A congruent melting peak at temperature 1801 ± 4.9 °C with ΔH = 65.2 ± 6.7 kJ/mol was detected for the Nd2S3 compound by the DSC method. The characteristics of the α-Nd2S3 → γ-Nd2S3 polymorphic transition are t = 1183 ± 1.8°С, and ΔH = 7.5 ± 0.3 kJ/mol. The γ-Nd2S3 phase obtained upon cooling during annealing at 800 °C is retained for up to 30 h, and then the γ-Nd2S3 → α-Nd2S3 transition occurs within 20 h. The microhardness of the phases is: α-Nd2S3 H = 451 ± 4 HV; γ-Nd2S3 H = 531 ± 4 HV. It was found by the TG method that the Nd10S14O phase thermally dissociates at temperatures above 1400 °C. The mass loss is 0.5 mass % at 1580 °C and 1.0 mass % at 1620 °C, but the samples remain single-phase ones after cooling. However, two impurity phases γ-Nd2S3-X and Nd2O2S appear in the Nd10S14O samples treated at temperatures above 1620 ± 20 °C. For samples of the Nd10S14O phase annealed in an argon atmosphere at temperatures of 1050, 1400, 1580 °C, a regular decrease in the unit cell parameters and optical band gap was recorded: 1050 °C a = 15.06291(28), c = 19.97864(35), Eg = 2, 63 eV, 1400 °C a = 15.04779(36), c = 19.97160(44), Eg = 2.64 eV; 1580 °C a = 15.03532(48), c = 19.94984(60), Eg = 2.51 eV. The microhardness of Nd10S14O is H = 549 ± 10 HV. The Nd2O2S phase has H = 593 ± 4 HV, Eg = 4.28 eV. The phase diagram of the Nd2S3 - Nd2O3 system from 1000 °C to the melt was constructed. The Nd2O2S phase melts congruently at 2050 ± 30 °C. Eutectics with coordinates 23 mol. % Nd2O3 (0.3484 Nd10S14O + 0.6516 Nd2O2S), t = 1553 ± 1.8°С; ΔH = 187 ± 19 J/g; 82 mol. % Nd2O3; (0.54 Nd2O2S + 0.46 Nd2O3), t = 1970 ± 30°С were obtained. The liquidus of the Nd2S3 - Nd2O3 system was built according to DSC data and calculated using the Redlich-Kister equation. The melting enthalpy of Nd2O2S ΔH = 67 kJ/mol was calculated using the Schroeder equation.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Wu, Pochang, Yeh, Enrong, Zyryanov V. Ya., Lee, Wei
Заглавие : Spatial and electrical switching of defect modes in a photonic bandgap device with a polymer-dispersed liquid crystal defect layer
Коллективы : Ministry of Science and Technology, Taiwan [NSC 101-2112-M-009-018-MY3, 103-2923-M-009-003-MY3, 102-2811-M-009-060]; Siberian Branch of the Russian Academy of Sciences [43, 24.29, 101]
Место публикации : Opt. Express: Optical Society of America, 2014. - Vol. 22, Is. 17. - P.20278-20283. - ISSN 1094-4087, DOI 10.1364/OE.22.020278
Примечания : Cited References: 19. - This work was financially sponsored by the Ministry of Science and Technology, Taiwan, through Grants NSC 101-2112-M-009-018-MY3, 103-2923-M-009-003-MY3 and 102-2811-M-009-060. V. Ya. Zyryanov would like to thank the Siberian Branch of the Russian Academy of Sciences (grants Nos. 43, 24.29, 101 and NSC-SB-RAS joint project).
Предметные рубрики: PHASE-SEPARATION
LIGHT
Аннотация: This paper investigates the spectral properties of a one-dimensional photonic crystal (PC) containing an inhomogeneous polymer- dispersed liquid crystal (PDLC) as a defect layer. Experimental results indicate that the voltage-induced reorientation of LC molecules between the light-scattering and transparent states in the PDLC enables the electrical tuning of the transmittance of defect-mode peaks in the spectrum of the PC/PDLC cell. Specifically, owing to the unique configuration of the spatial distribution of LC droplet sizes in the defect layer, a concept concerning the spatial switching in the wavelength of defect modes is proposed. As a result, the PC/PDLC hybrid cell is suggested as a potential element for realizing an electrically tunable and spatially switchable photonic bandgap device, which is polarizer-free and requires no alignment layers in the fabrication process.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Wang H. T., Timofeev I. V., Chang K., Zyryanov V. Ya., Lee W.
Заглавие : Tunable narrow-bandpass filter based on an asymmetric photonic bandgap structure with a dual-mode liquid crystal
Коллективы : Ministry of Science and Technology of Taiwan [NSC 101-2112-M-009-018-MY3, NSC 103-2923-M-009-003-MY3]; Russian Foundation for Basic Research [14-02-3124814]; Siberian Branch of the Russian Academy of Sciences [43, 24.29 and 101]
Место публикации : Opt. Express: Optical Society of America, 2014. - Vol. 22, Is. 12. - P.15097-15103. - ISSN 1094-4087, DOI 10.1364/OE.22.015097
Примечания : Cited References: 23. - This work was supported by the Ministry of Science and Technology of Taiwan through Grant No. NSC 101-2112-M-009-018-MY3 as well as Grant No. NSC 103-2923-M-009-003-MY3 dedicated to a joint project between Taiwan and Russia. Both I. V. Timofeev and V. Ya. Zyryanov would like to thank the Russian Foundation for Basic Research (project No. 14-02-3124814) and the Siberian Branch of the Russian Academy of Sciences (grants Nos. 43, 24.29 and 101).
Предметные рубрики: DEVICE
LAYER
CELL
Аннотация: A one-dimensional asymmetric photonic crystal with dual-frequency liquid crystal as a central defect layer was demonstrated. Such asymmetric structure was characterized by the dramatic increase in intensity of the electric field of light localized at the overlapped photonic bandgap edges, thereby enhancing the observed transmittance of the spectral windows originating from the defect layer. The defect layer was made of a dual-mode liquid crystal that exhibited not only electrical tunability and switchability but also optical bistability. Consequently, tunable and bistable defect modes can be realized in the photonic structure. This asymmetric photonic crystal structure is promising and should be further explored for photonic device applications. (C) 2014 Optical Society of America
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10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zhandun V. S.
Заглавие : The magnetic, electronic, optical, and structural properties of the AB2O4 (A = Mn, Fe, Co; B = Al, Ga, In) spinels: Ab initio study
Место публикации : J. Magn. Magn. Mater. - 2021. - Vol. 533. - Ст.168015. - ISSN 03048853 (ISSN), DOI 10.1016/j.jmmm.2021.168015
Примечания : Cited References: 38. - The reported study was funded by Russian Foundation for Basic Research , Government of Krasnoyarsk Territory , Krasnoyarsk Regional Fund of Science to the research project № 19-42-240016: «Control of structural, magnetic, electronic, and optical properties by pressure and intercalation into functional compounds with a spinel structure containing 3d and 4f ions» The calculations were performed with the computer resources of “Complex modeling and data processing research installations of mega-class” SRC “Kurchatovsky Institute” (http://ckp.urcki.ru)
Аннотация: The effect of cation composition on the magnetic, electronic, optical, and structural properties of the spinel oxides AB2O4 (A = Fe, Mn, Co; B = Al, Ga, In) were studied within DFT-GGA + U approximation. The spinels were considered both in the normal and inverse structure. FeB2O4 (B = Al, Ga, In) spinels have an inverse structure, whereas AB2O4 (A = Mn, Co; B = Al, Ga, In) prefer a normal structure. We find that the studied spinels are antiferromagnetic materials with the composition-dependent bandgap. The bandgap width is determined by the minimum of the conductive s-band formed by B-site cations states and can be increased by the applied pressure. The microscopic mechanisms of the relationship between composition, structural and electronic properties are analyzed. The ability to manipulate the structural, electronic, and optical properties is attributed to the different s-orbital energies and sizes of the B-site cations.
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