Raman and Hyper-Rayleigh Scattering in Lithium Tetraborate Crystals

Experimental studies of Raman scattering and the infrared reflection spectra of lithium tetraborate crystals were carried out within a broad temperature range with various polarization geometries. The crystals studied are characterized by record values of radiation resistance, transparence within a broad spectral range including the ultraviolet region, and nonlinear optical properties. A group-theoretical analysis of the vibrational spectra of this crystal was performed and fundamental vibrational terms were assigned to the symmetry types of the point group as well as the polarizations of the corresponding modes. The effective Raman cross section was measured and was found to be one order of magnitude higher than those of the known crystals, in which the stimulated Raman scattering (SRS) was observed. The nonlinear optical and electrooptical coefficients were evaluated and were found to be consistent with the results of independent measurements. The effect of a drastic increase in the intensity of quasi-elastic light scattering at 253 K was registered. It was associated with the phase transition that consists of the disordering of lithium ions with respect to the rigid skeleton. The formation energy for Frenkel defects in the lithium sublattice and the activation energy of the ionic conduction when heating the sample were calculated from the obtained temperature dependences of the intensity of quasielastic and hyper-Rayleigh light scattering.     

球状晶体中的拉曼散射和布拉格衍射(英文)

The results of optical properties investigations for some types of globular crystals, including artifical opals and amorphous substances, constructed from the globular nanoclusters are represented. The spectra of light reflection from the surface of received opals have investigated at different incident angle（under mirror-reflection geometry）： 0, 20, 30, 45 and 60 degree.     

Stimulated Low-Frequency Raman Scattering in a Single-Crystal Diamond with a Buried Graphitized Layer

Optics and Spectroscopy - The results of experimental observation of stimulated low-frequency Raman scattering (SLFRS) in a single-crystal diamond with a buried graphitized layer created as a...     

Raman Light Scattering in Silicon with the Crystal Structure Damaged by Implantation of Carbon Ions

Optics and Spectroscopy - Raman scattering spectra from silicon whose crystal lattice is damaged by implantation of carbon ions with an energy of 40 keV and dose 5 × 1016 cm–2 have been...     

Microstructure of Si Crystals Subjected to Irradiation with High-Energy H+ Ions and Heat Treatment by High-Resolution Three-Crystal X-Ray Diffraction and Transmission Electron Microscopy

Physics of the Solid State - The structural features of the formation of radiation defects in proton-implanted layers of silicon plates during their heat treatment have been studied. New data on...     

Ce:BaTiO3晶体电光和二倍频系数的拉曼散射测量

从极性晶体晶格振动的理论出发,推导出正交系以上晶系的晶体的拉曼散射效率与晶体电光系数和二倍频系数的关系,测量了Ｃｅ：ＢａＴＩＯ３和ＢａＴｉＯ３晶体各纵、横模的偏振拉曼谱。在此基础上,计算出这两种晶体的电光系数ｒ３３、ｒ５１和二倍频系数ｄ３３、ｄ１５。结果表明：掺微量Ｃｅ元素对ＢａＴｉＯ３晶体电光系数和二倍频系数影响不大。     

Basic Requirements of Spin-Flip Raman Scattering on Excitonic Resonances and Its Modulation through Additional High-Energy Illumination in Semiconductor Heterostructures

We describe the major requirements to experimentally perform and observe resonant spin-flip Raman scattering on excitonic resonances in low-dimensional semiconductors. We characterize in detail the properties of this resonant light scattering technique and evaluate the criteria, which must be fulfilled by the experimental setup and the semiconductor sample studied to be able to observe a spin-flip scattering process. We also demonstrate the influence of additional unpolarized laser illumination with energies, which exceed considerably the band gap energy of the semiconductor nanostructure under study, on the resonantly excited electron spin-flip scattering in InAs-based quantum dot ensembles as well as on the paramagnetic Mn-ion spin-flip in (Zn,Mn)Se/(Zn,Be)Se quantum wells.     

Titanium Ions in the Diamond Structure: Model and Experimental Evidence

In this paper, we have presented a set of experiments on the high-pressure–high-temperature treatment of synthetic diamonds grown in a Fe–Ni–C system with additional titanium as a nitrogen getter. The defect responsible for the 440.3 nm photoluminescence system related to the electron paramagnetic resonance N3 center has been first created. This finding is an evidence in favor of an earlier assumption of incorporating the titanium ion in the structure of the N3/440.3 nm centers.     

Nature of Local Symmetry Violations of Ions in the Magnetic Subsystem of Magnetoplumbite Crystal,According to Raman Scattering Spectroscopy Data

The structure of an M-type lead hexaferrite (magnetoplumbite) crystal is studied via the diffraction of synchrotron radiation. The crystal model contains two iron ions positions with dynamic disorder. The dynamics of the crystal lattice in the temperature range of 80 to 775 K is studied by Raman scattering. Particular attention is given to the discussing the nature of the local disorder of iron ions in the trigonal bipyramidal environment of oxygen ions.     

Photoluminescence Spectra of ZnS:Al Crystals Annealed in a Melt with Bismuth and Chlorine Ions

The results of the temperature investigations (77–520 K) of the photoluminescence (PhL) of lowohmage ZnS monocrystals annealed in bismuthbased melts are presented. It is shown that the ion composition of the annealing medium produces a determining effect on the formation of an impuritydefect composition of the radiative centers. The dominant contribution to the PhL radiation is attributed to the centers based on the vacancies of sulfur and zinc and aluminum and chlorine. In the nearsurface region and in the bulk of the crystal, the PhL spectra differ. The PhL spectra in the nearsurface region of the crystal are determined by the complex bismuth centers and correspond to the characteristic features of the intracenter transitions. We propose two possible models of radiative centers: (V_Zn ^/Bi_Zn )^times and DX centers. It has been found that the simultaneous action of the radiation from a pulsed nitrogen laser and the heating at a temperature from 410 to 518 K destroy the radiative bismuth centers and lead to the formation of precipitates Bi₂S₃ and BiS₂.     

Characterization of Microstructure and Stability of Precipitation in SIMP Steel Irradiated with Energetic Fe Ions

A type of home-made reduced activation martensitic steel, high silicon(SIMP) steel, is homogeneously irradiated with energetic Fe ions to the doses of 0.1, 0.25 and 1 displacement per atom(dpa), respectively, at 300°C and1 dpa, at 400℃. Microstructural changes are investigated in detail by transmission electron microscopy with cross-section technique. Interstitial defects and defect clusters induced by Fe-ion irradiation are observed in all the specimens under different conditions. It is found that with increasing irradiation temperature, size of defect clusters increases while the density drops quickly. The results of element chemical mapping from the STEM images indicate that the Si element enrichment and Ta element depletion occur inside the precipitates in the matrix of SIMP steel irradiated to a dose of 1 dpa at 300℃. Correlations between the microstructure and irradiation conditions are briefly discussed.     

Erratum to: Magnetic Properties and Spin Crossover in Transition Metal Oxides with d5 Ions at High Pressures

Journal of Experimental and Theoretical Physics - erratum     

Transformations of the Spectrum of an Optical Phonon Excited in Raman Scattering in the Bulk of Diamond by Ultrashort Laser Pulses with a Variable Duration

JETP Letters - A spontaneous Raman signal at the frequency of the triply degenerate optical phonon of diamond is observed in the photoluminescence spectrum under the pre-filamentation excitation of...     

利用拉曼散射、共振拉曼散射及瑞利散射对ZnSe-ZnS多量子阱材料光谱的判定

利用拉曼散射、共振拉曼散射及瑞利散射对ＺｎＳｅ┐ＺｎＳ多量子阱材料光谱的判定赵福潭王淑梅苏锡安刘行仁（中国科学院激发态物理开放研究实验室长春１３００２１）ＤｉｓｔｉｎｇｕｉｓｈｉｎｇｏｆＬｕｍｉｎｅｓｃｅｎｃｅＳｐｅｃｔｒａｉｎＺｎＳｅ┐ＺｎＳＭＱＷ...     

Timing Jitter and Frequency Shift in Dispersion-Managed Soliton Systems with Raman Scattering Effect

We have studied the timing jitter in dispersion-managed soliton systems with a Gaussian pulse by two methods. Firstly, the timing jitter expressions for dispersion-managed soliton are derived by use of the perturbed variational method. By analyzing and simulating the timing jitter expressions, one can find that the timing jitter is induced by the amplifier spontaneous emission noise, the frequency shift, etc. The chirp sign, the soliton self-frequency shift, and the filters action also have effects on the timing jitter. Secondly, the timing jitter is calculated and analyzed by the moment method. The results of the two methods are proved to be consistent.     

Single Centers and Dimers of Impurity Holmium Ions in Synthetic Forsterite Crystals: High-Resolution Spectroscopy

Optics and Spectroscopy - High-resolution low-temperature absorption spectra in the region of the 5I8 → 5I7, 6, 5, 4, 5F5 transitions in impurity Ho3+ ions in...     

Erratum to: Natural Vibrations of Micropolar Elastic Flexible Plates and Shallow Shells

Acoustical Physics - An Erratum to this paper has been published: https://doi.org/10.1134/S1063771022340012