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1.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kostyukov A. S., Isaev I. L., Ershov A. E., Gerasimov V. S., Polyutov S. P., Karpov S. V.
Заглавие : Part II. Nanobubbles around plasmonic nanoparticles in terms of modern simulation modeling: what makes them kill the malignant cells?
Коллективы : Ministry of Science and High Education of Russian Federation [FSRZ-2020-0008]; RFBRRussian Foundation for Basic Research (RFBR); Krasnoyarsk Territory and Krasnoyarsk Regional Fund of Science [20-42-240003]
Место публикации : J. Phys. D. - 2022. - Vol. 55, Is. 17. - Ст.175402. - ISSN 0022-3727, DOI 10.1088/1361-6463/ac4c1f. - ISSN 1361-6463(eISSN)
Примечания : Cited References: 49. - The research was supported by the Ministry of Science and High Education of Russian Federation (Project No. FSRZ-2020-0008), and was funded by RFBR, Krasnoyarsk Territory and Krasnoyarsk Regional Fund of Science, Project No. 20-42-240003
Предметные рубрики: STRESS WAVES
LASER
MEMBRANE
DAMAGE
DEATH
LYSIS
Аннотация: We have established numerically the physical pattern and conditions for formation of nanosized bubbles in aqueous medium around biocompatible plasmonic nanoparticles (NPs) selectively bound to the membrane of the malignant cells by means of DNA-aptamers under the action of picosecond laser radiation. The results obtained are based on the finite volume method and hydrodynamic models underlying the ANSYS Fluent package with extended capabilities. We have found the main features and previously unknown dominant factors of the damage effect on the cell membrane at the moment of the bubble nucleation around the plasmonic NPs of different types taking into account the influence of the closely located membrane. Information on the kinetics of spatial distribution of pressure, temperature and the relative proportion of vapor in the 'nanoparticle-membrane-medium' system have been obtained. The attention is drawn to the advantages of using biocompatible, perfectly absorbing core–shell plasmonic NPs for anti-tumor therapy characterized by an increased mechanical effect on malignant cell membranes at lower laser radiation intensity and the spectral position of their plasmon resonance (λ = 700 nm) in the hemoglobin transparency range. This ensures penetration of laser radiation deep into tissues. The paper is provided with an extensive review of key publications and the state-of-art in this area.
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2.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Liu, Yan Rong, Wu, Yong, Wang, Jian Guo, Vendrell, Oriol, Kimberg V., Zhang, Song Bin
Заглавие : Electron-rotation coupling in diatomics under strong-field excitation
Место публикации : Phys. Rev. A. - 2020. - Vol. 102, Is. 3. - Ст.033114. - ISSN 2469-9926, DOI 10.1103/PhysRevA.102.033114. - ISSN 2469-9934(eISSN)
Примечания : Cited References: 78. - S.B.Z. thanks H. D. Meyer for his helpful instructions of Wigner-DVR in MCTDH. Grants from the National Basic Research Program of China (2017YFA0403200), NSFC (No. 11604197, No. 11974230, and No. 11934004), the Science Challenge Program of China (TZ2018005 and TZ2016005) are acknowledged. V.K. acknowledges financial support from Swedish Research Council (VR) and the Ministry of Science and High Education of Russian Federation, Project No. FSRZ2020-0008.
Предметные рубрики: REAL-TIME OBSERVATION
DYNAMICS
LASER
ULTRAFAST
MOLECULES
Аннотация: he photoexcitation and photodissociation of diatomic molecules by intense pulse lasers has been the subject of extensive investigations over the past decades. However, the usually employed theoretical framework neglects the coupling between the molecular rotational angular momentum (R) and the angular momentum of the electrons projected onto the molecular axis Ω=Λ+Σ, which results in the known Λ-doubling phenomenon in high-resolution electronic spectra of diatomic molecules. While neglecting this coupling is an excellent approximation in the weak-field or perturbative regime owing to the large mass difference between the rotating atoms and the electrons, the approximation breaks down for intense laser pulses because of the repeated Rabi cycling of the electronic transitions, which can have a significant effect on the rotational degrees of freedom of the molecule. By correcting the transition dipole matrix elements and introducing angular basis sets based on Wigner D functions, the conventional theoretical treatment is generalized to a universal description valid for both the weak- and strong-field regimes. The theoretical treatment developed here is applied to the ∣1Σ› to ∣1Π› transitions in diatomic systems. Our results reveal that, for field intensities resulting in about one Rabi cycling for extreme ultraviolet or x-ray transitions, the theoretical predictions by the conventional theoretical frame need to be corrected when considering observables such as the molecular alignment and the angular distribution of the photofragments.
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3.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Jiang, Xingxing, Wang, Naizheng, Molokeev M. S., Wang, Wei, Guo, Shibin, Huang, Rongjin, Li, Laifeng, Hu, Zhanggui, Lin, Zheshuai
Заглавие : The anisotropic thermal expansion of non-linear optical crystal BaAlBO3F2 below room temperature
Место публикации : Front. Chem. - 2018. - Vol. 6. - Ст.252. - ISSN 2296-2646, DOI 10.3389/fchem.2018.00252
Примечания : Cited References: 31. - This work was supported by the National Scientific Foundations of China (Grants 11474292, 51702330, 11611530680, 91622118, and 91622124), Russian Foundation for Basic Research (Grant 17-52-53031), the Special Foundation of the Director of Technical Institute of Physics and Chemistry (TIPC) and the Youth Innovation Promotion Association, CAS (outstanding member for ZL and Grant 2017035 for XJ).
Предметные рубрики: LASER
GENERATION
PSEUDOPOTENTIALS
COEFFICIENTS
YAG
Ключевые слова (''Своб.индексиров.''): babf--anisotropic thermal expansion--phonon stimulation--nlo optical--property--low temperature
Аннотация: Thermal expansion is a crucial factor for the performance of laser devices, since the induced thermal stress by laser irradiation would strongly affect the optical beam quality. For BaAlBO3F2 (BABF), a good non-linear optical (NLO) crystal, due to the highly anisotropic thermal expansion its practical applications are strongly affected by the “tearing” stress with the presence of local overheating area around the laser spot. Recently, the strategy to place the optical crystals in low-temperature environment to alleviate the influence of the thermal effect has been proposed. In order to understand the prospect of BABF for this application, in this work, we investigated its thermal expansion behavior below room temperature. The variable-temperature XRD showed that the ratio of thermal expansion coefficient between along c- and along a(b)- axis is high as 4.5:1 in BABF. The Raman spectrum combined with first-principles phonon analysis revealed that this high thermal expansion anisotropy mainly ascribe to progressive stimulation of the respective vibration phonon modes related with the thermal expansion along a(b)- and c-axis. The good NLO performance in BABF can be kept below room temperature. The work presented in this paper provides an in-depth sight into the thermal expansion behavior in BABF, which, we believe, would has significant implication to the manipulation in atomic scale on the thermal expansion of the materials adopted in strong-field optical facility.
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4.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Malakhovskii A. V., Sukhachev A. L., Sokolov V. V., Kutsak T. V., Bondarev V. S., Gudim, I. A.
Заглавие : Magneto-optical activity of f–f transitions in ErFe3(BO3)4 and ErAl3(BO3)4 single crystals
Коллективы : Russian Foundation for Basic Researches [12-02-00026], President of Russia Grant [Nsh-2886.2014.2]
Место публикации : J. Magn. Magn. Mater.: Elsevier, 2015. - Vol. 384. - P.255-265. - ISSN 0304-8853, DOI 10.1016/j.jmmm.2015.02.051. - ISSN 1873-4766
Примечания : Cited References: 44. - The work was supported by the Russian Foundation for Basic Researches Grant 12-02-00026 and by the President of Russia Grant no. Nsh-2886.2014.2.
Предметные рубрики: CIRCULAR-DICHROISM SPECTRA
GREEN UP-CONVERSION
SPECTROSCOPIC PROPERTIES
OPTICAL-PROPERTIES
LASER
Er3+
ABSORPTION
GROWTH
IONS
GdFe3(BO3)4
Ключевые слова (''Своб.индексиров.''): magnetic circular dichroism--natural circular dichroism--rare earth ferroborates--rare earth alumoborates--electronic structure
Аннотация: Absorption, magnetic circular dichroism and natural circular dichroism spectra of ErFe3(BO3)4 and ErAl3(BO3)4 single crystals were measured as a function of temperature in the range of 90–293 K. It was found out that magneto-optical activity of the same f–f transitions in the studied crystals substantially differed and their temperature dependences did not follow the Curie–Weiss law in contrast to the properties of allowed transitions. The observed phenomena were accounted for by the nature of f–f transitions allowance. Properties of the transition 4I15/2→4S3/2 were studied in detail. In particular, the Zeeman splitting and the natural optical activity of the absorption lines composed of the transition were determined. The vibronic line with the very large natural optical activity was revealed and identified. Two nonequivalent Er3+ ion positions with the opposite chirality were found out in one of the excited states. Polarization properties of the 4I15/2→4S3/2 transition in the ErFe3(BO3)4 crystal have shown that the local symmetry of Er3+ ion in this crystal in the range of 90–293 K is lower than the D3 one. From the heat capacity measurements it was revealed, that the first order structural phase transition to lower symmetry occurred in ErFe3(BO3)4 at 433–439 K.Поглощение, магнитный циркулярный дихроизм и спектры природного кругового дихроизма монокристаллов ErFe3(BO3)4 и ErAl3(BO3)4 были измерены в зависимости от температуры в диапазоне 90-293 К. Было обнаружено, что по магнитооптической активности одни и те жеF-F переходы в исследованных кристаллах существенно отличаются и их температурные зависимости не следовать закону Кюри-Вейсса в отличие от свойств разрешенных переходов. Наблюдаемые явления были учтены по характеру F-Fпереходов. Свойства перехода 4I15 / 2 → 4S3 / 2 были детально изучены. В частности, расщепление Зеемана и явление естественной оптической активности линий поглощения, состоящих в переходе были полны решимости. Вибронная линия очень большой естественной оптической активности выявлена и идентифицирована. Две неэквивалентных позиций ионовEr3 + с противоположной хиральности были найдены в одном из возбужденных состояний. Поляризационные свойства 4I15 / 2 → 4S3 / 2 перехода в ErFe3(BO3)4 кристалла показали, что локальная симметрия ионов Er3 + в этом кристалле в диапазоне 90-293 К ниже, чем D3. Из измерений теплоемкости Было обнаружено, что структурный фазовый переход первого типа к более низкой симметрии произошел в ErFe3(BO3) 4 при 433-439 К. Ключевые слова: Магнитный круговой дихроизм; Природные круговой дихроизм; Редкоземельные ферроборатов; Редкоземельныеalumoborates; Электронная структура; 44 источника.
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5.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Pashchenko M. I., Bedarev V. A., Merenkov D. N., Savina Yu. O., Pashchenko V. O., Gnatchenko S. L., Bezmaternykh L. N., Temerov V. L.
Заглавие : Magneto-optical properties of terbium iron borate
Место публикации : Appl. Optics: Optical Society of America, 2014. - Vol. 53, Is. 10. - P.B116-B120. - ISSN 1559-128X, DOI 10.1364/AO.53.00B116. - ISSN 2155-3165
Примечания : Cited References: 19
Предметные рубрики: GENERATION
CRYSTALS
LASER
Аннотация: The Faraday effect induced by an external magnetic field in TbFe3(BO3)4 and TbAl3(BO3)4 borates at a wavelength 633 nm has been investigated. It was found that the terbium subsystem brings the dominant magnetic contribution to the Faraday rotation at low temperatures in borate TbFe3(BO3)4. For both TbFe3(BO3)4 and TbAl3(BO3)4 the magneto-optical coefficients of the terbium subsystem were determined.
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6.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Cherepakhin A. V., Zaitsev A. I., Aleksandrovsky A. S., Zamkov A. V.
Заглавие : Optical and nonlinear optical properties of orthorhombic BiB3O6
Место публикации : Opt. Mater.: Elsevier Science BV, 2012. - Vol. 34, Is. 5. - P.790-792. - ISSN 0925-3467, DOI 10.1016/j.optmat.2011.11.004
Примечания : Cited References: 13. - The work was supported by Ministry of Education and Science of Russian Federation (Contract 16.740.11.0150), Grant of President of Russian Federation for support of leading scientific schools No. SS-4645.2010.2, Grant No. RNP.2.1.1.3455, Project 3.9.1 of PSB RAS, and Projects No. 27.1 and No. 5 of SB RAS.
Предметные рубрики: BISMUTH BORATE BIB3O6
CRYSTAL
LASER
GENERATION
GROWTH
BIBO
Ключевые слова (''Своб.индексиров.''): orthorhombic bismuth triborate delta-bibo--refractive indices--nonlinear optical coefficients--nonlinear optical materials--phase matching
Аннотация: Dispersion of refraction coefficients of orthorhombic BiB3O6 in the wavelength range between 435.8 and 1060 nm is studied, nonlinear optical coefficients are determined, and phase matching angles, angular and spectral bandwidths for second harmonic generation processes are calculated. delta-BiBO may be suitable for doubling of lasers with a wavelength in the 1.3 mu m region as well as the matrix for self-doubling lasing media. (C) 2011 Elsevier B.V. All rights reserved.
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7.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Atuchin V. V., Chimitova O. D., Gavrilova T. A., Molokeev M. S., Kim S. J., Surovtsev N. V., Bazarov B. G., Bazarova Zh.G.
Заглавие : Synthesis, structural and vibrational properties of microcrystalline RbNd(MoO4)(2)
Коллективы : International Conference on Crystal Growth, International Conference on Vapor Growth and Epitaxy
Место публикации : J. Cryst. Growth: Elsevier Science BV, 2011. - Vol. 318, Is. 1. - P.683-686. - ISSN 0022-0248, DOI 10.1016/j.jcrysgro.2010.09.076
Примечания : Cited References: 26
Предметные рубрики: MOLYBDENUM TRIOXIDE
DOUBLE MOLYBDATES
CRYSTAL-STRUCTURE
GROWTH
LASER
MOO3
Ключевые слова (''Своб.индексиров.''): crystal structure--solid state synthesis--molybdate
Аннотация: Rubidium neodymium dimolybdate, RbNd(MoO4)(2), microcrystals have been fabricated by solid state synthesis at T=550-600 degrees C by t=324 ks. Crystal structure of RbNd(MoO4)(2) has been refined by Rietveld method in space group Pbcn with cell parameters a = 5.1772(1) angstrom, b = 18.7293(4) angstrom, and c = 8.2774(1) angstrom (R-B=5.05%). The crystal structure of RbNd(MoO4)(2) consists of layers of MoO4 tetrahedrons cornersharing with NdO8 square antiprisms. These layers are perpendicular to b-axis of the unit cell. About 20 narrow Raman lines have been observed in Raman spectrum recorded for RbNd(MoO4)(2) powder sample. (C) 2010 Elsevier B.V. All rights reserved.
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8.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Vetrov S.Ya., Timofeev I. V., Rudakova N. V.
Заглавие : Band structure of a two-dimensional resonant photonic crystal
Место публикации : Phys. Solid State: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2010. - Vol. 52, Is. 3. - P.527-532. - ISSN 1063-7834, DOI 10.1134/S1063783410030133
Примечания : Cited References: 16. - This study was supported by the Council on Grants from the President of the Russian Federation (grant nos. 3818.2008.3 and 1292.2008.2), the Ministry of Education and Science of the Russian Federation within the framework of the program "Development of the Scientific Potential of the Higher School" (RNP no. 2.1.1/3455), the Presidium of the Russian Academy of Sciences (project no. 27.1), and the Siberian Branch of the Russian Academy of Science (project nos. 5 and 144).
Предметные рубрики: TRANSMISSION
LASER
Аннотация: The band structure of two-dimensional resonant photonic crystals of two types has been calculated using the expansion of eigenfunctions in plane waves. Crystals of one type consist of infinite dielectric cylinders forming a square lattice filled with a resonant gas, and crystals of the other type consist of infinite cylindrical holes filled with a resonant gas and forming a square lattice in a dielectric matrix. It has been shown that, in both cases, the dispersion of a resonant gas in combination with the dispersion of a two-dimensional structure with a photonic band gap leads to the appearance of an additional narrow transmission band near the edge of the band gap or an additional band gap in the continuous spectrum of the photonic crystal. The calculations performed have demonstrated that new dispersion properties substantially depend on the density of the resonant gas, the position of the resonant frequency with respect to the edge of the band gap, and the direction of propagation of electromagnetic waves.
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9.

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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10.

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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11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Vorotynov A. M., Petrakovskii G. A., Shiyan Ya. G., Bezmaternykh L. N., Temerov V. E., Bovina A. F., Aleshkevych P.
Заглавие : Electron paramagnetic resonance of Mn2+ ions in single crystals of yttrium aluminum borate YAl3(BO3)4
Место публикации : Phys. Solid State: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2007. - Vol. 49, Is. 3. - P463-466. - ISSN 1063-7834, DOI 10.1134/S1063783407030122
Примечания : Cited References: 11
Предметные рубрики: HUNTITE STRUCTURE
GROWTH
LASER
Аннотация: Single crystals of yttrium aluminum borate YAl3 (BO3)(4) doped with manganese ions are studied using electron paramagnetic resonance spectroscopy. It is shown that manganese ions introduced at low concentrations into the sample predominantly occupy yttrium ion sites in the crystal structure. The shape of the electron paramagnetic resonance spectrum unambiguously indicates that the valence of manganese ions in this case is equal to 2+. The parameters of the spin Hamiltonian of Mn2+, ions in the YAl3(BO3)(4) matrix are determined at room temperature. The magnitude and sign of the fine structure parameter D allow the conclusion that the YAl3(BO3)(4) single crystals doped with manganese ions have a strong crystal field at the yttrium ion sites and L easy-axis anisotropy.
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12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Popova M. N., Chukalina E. P., Stanislavchuk T. N., Malkin B. Z., Zakirov A. R., Antic-Fidancev E., Popova E. A., Bezmaternykh L. N., Temerov V. L.
Заглавие : Optical spectra, crystal-field parameters, and magnetic susceptibility of multiferroic NdFe3(BO3)(4)
Разночтения заглавия :авие SCOPUS: Optical spectra, crystal-field parameters, and magnetic susceptibility of multiferroic Nd Fe3 (B O3) 4
Место публикации : Phys. Rev. B: AMERICAN PHYSICAL SOC, 2007. - Vol. 75, Is. 22. - Ст.224435. - ISSN 1098-0121, DOI 10.1103/PhysRevB.75.224435
Примечания : Cited References: 22
Предметные рубрики: IRON BORATE GDFE3(BO3)(4)
CRYSTALLIZATION
SPECTROSCOPY
LASER
ND3+
Аннотация: We report high-resolution optical absorption spectra for NdFe3(BO3)(4) trigonal single crystal, which is known to exhibit a giant magnetoelectric effect below the temperature of magnetic ordering T-N=33 K. The analysis of the temperature-dependent polarized spectra reveals the energies and, in some cases, symmetries and exchange splittings of Nd3+ 84 Kramers doublets. We perform crystal-field calculations starting from the exchange-charge model, obtain a set of six real crystal-field parameters, and calculate wave functions and magnetic g factors. In particular, the values g(perpendicular to)=2.385 and g(parallel to)=1.376 were found for the Nd3+ ground-state doublet. We obtain B-loc=7.88 T and parallel to J(FN)parallel to=0.48 K for the values of the local effective magnetic field at liquid-helium temperatures at the Nd3+ site and the Nd-Fe exchange integral, respectively, using the experimentally measured Nd3+ ground-state splitting of 8.8 cm(-1). To check the reliability of our set of crystal-field parameters, we model the magnetic susceptibility data from literature. A dimer containing two nearest-neighbor iron ions in the spiral chain is considered to partly account for quasi-one-dimensional properties of iron borates, and then the mean-field approximation is used. The results of calculations with the exchange parameters for Fe3+ ions J(nn)=-6.25 K (intrachain interactions) and J(nnn)=-1.92 K (interchain interactions) obtained from fitting agree well with the experimental data.
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13.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Malakhovskii A. V., Edelman I. S., Sokolov A. E., Temerov V. L., Gnatchenko S. L., Kachur I. S., Piryatinskaya V. G.
Заглавие : Optical absorption spectrum and local symmetry of Tm3+ ion in TmAl3(BO3)(4) crystal
Разночтения заглавия :авие SCOPUS: Optical absorption spectrum and local symmetry of Tm3+ ion in TmAl3(BO3)4 crystal
Место публикации : Phys. Lett. A: ELSEVIER SCIENCE BV, 2007. - Vol. 371, Is. 3. - P254-258. - ISSN 0375-9601, DOI 10.1016/j.physleta.2007.06.025
Примечания : Cited References: 10
Предметные рубрики: LASER
HUNTITE
Ключевые слова (''Своб.индексиров.''): rare earth compounds--spectroscopy--site symmetry--rare earth compounds--site symmetry--spectroscopy
Аннотация: With the help of group theory analysis of absorption spectra of the transition H-3(6) - F-3(3) of Tm3+ ion in TmAl3(BO3)(4) crystal, measured at several temperatures from 1.8 till 293 K, it has been shown, that the local symmetry of the Tm3+ environment is C-3 and it decreases to C-1 at a low temperature. Effective selection rules and polarizations of lines at high enough temperatures (when the line-width is larger than the splitting in C-3 symmetry) have been obtained. (c) 2007 Elsevier B.V. All rights reserved.
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14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Fausti D., Nugroho A. A., van Loosdrecht PHM, Klimin S. A., Popova M. N., Bezmaternykh L. N.
Заглавие : Raman scattering from phonons and magnons in RFe3(BO3)(4)
Разночтения заглавия :авие SCOPUS: Raman scattering from phonons and magnons in RFe3 (BO3) 4
Место публикации : Phys. Rev. B: AMER PHYSICAL SOC, 2006. - Vol. 74, Is. 2. - Ст.24403. - ISSN 1098-0121, DOI 10.1103/PhysRevB.74.024403
Примечания : Cited References: 26
Предметные рубрики: IRON BORATE GDFE3(BO3)(4)
LIGHT-SCATTERING
CRYSTALS
ND
CRYSTALLIZATION
TRANSITIONS
GENERATION
LASER
Аннотация: Inelastic light scattering spectra of several members of the RFe3(BO3)(4) family reveal a cascade of phase transitions as a function of temperature, starting with a structural, weakly first-order, phase transition followed by two magnetic phase transitions. Those consist of the ordering of the Fe-spin sublattice, revealed by all the compounds, and a subsequent spin-reorientational transition for GdFe3(BO3)(4). The Raman data evidence a strong coupling between the lattice and magnetic degrees of freedom in these borates. The Fe-sublattice ordering leads to a strong suppression of the low-energy magnetic scattering, and a multiple peaked two-magnon scattering continuum is observed. Evidence for short-range correlations is found in the "paramagnetic" phase by the observation of a broad magnetic continuum in the Raman data, which persists up to surprisingly high temperatures.
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15.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Popov A. K., Myslivets S. A., Gao J. Y., Zhang H. Z., Wellegehausen B.
Заглавие : Inversionless gain in a three-level system driven by a strong field and collisions
Место публикации : Chin. Phys. - 2000. - Vol. 9, Is. 2. - P.124-130. - ISSN 1009-1963
Примечания : Cited References: 45
Предметные рубрики: ELECTROMAGNETICALLY INDUCED TRANSPARENCY
POPULATION-INVERSION
LIGHT AMPLIFICATION
QUANTUM COHERENCE
REFRACTIVE-INDEX
LASER
INTERFERENCE
TRANSITIONS
SODIUM
ATOMS
Аннотация: Inversionless gain in a degenerate three-level system driven by a strong external field and by collisions with a buffer gas is investigated. The mechanism of population distribution in upper laser level, contributed by the collision transfer, as well as by relaxation, induced by pressure of a buffer gas, is discussed in detail. Explicit formulae for analysis of optimal conditions are derived. The idea developed here for the incoherent pump could be generalized to other systems.
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16.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Alekseev K. N., Berman G. P., Campbell D. K., Cannon E. H., Cargo M. C.
Заглавие : Dissipative chaos in semiconductor superlattices
Место публикации : Phys. Rev. B: AMERICAN PHYSICAL SOC, 1996. - Vol. 54, Is. 15. - P10625-10636. - ISSN 0163-1829, DOI 10.1103/PhysRevB.54.10625
Примечания : Cited References: 89
Предметные рубрики: NEGATIVE DIFFERENTIAL CONDUCTIVITY
INJECTED SIGNAL
BLOCH OSCILLATIONS
COLLECTIVE EXCITATIONS
DETERMINISTIC CHAOS
MINIBAND TRANSPORT
SURFACE-PLASMONS
TIME-SERIES
LASER
VELOCITY
Аннотация: We consider the motion of ballistic electrons in a miniband of a semiconductor superlattice (SSL) under the influence of an external, time-periodic electric field. We use a semiclassical, balance-equation approach, which incorporates elastic and inelastic scattering (as dissipation) and the self-consistent field generated by the electron motion. The coupling of electrons in the miniband to the self-consistent held produces a cooperative nonlinear oscillatory mode which, when interacting with the oscillatory external field and the intrinsic Bloch-type oscillatory mode, can lead to complicated dynamics, including dissipative chaos. For a range of values of the dissipation parameters we determine the regions in the amplitude-frequency plane of the external field in which chaos can occur. Our results suggest that for terahertz external fields of the amplitudes achieved by present-day free-electron lasers, chaos may be observable in SSL's. We clarify the nature of this interesting nonlinear dynamics in the superlattice-external-field system by exploring analogies to the Dicke model of an ensemble of two-level atoms coupled with a resonant cavity field, and to Josephson junctions.
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