научный журнал по физике Оптика и спектроскопия ISSN: 0030-4034

GAI ZHANG, MIN TIAN — 2014 г.

A rapid strategy for the analysis of gold and silver in blister copper by inductively coupled plasma optical emission spectrometry (ICP-OES) was firstly proposed. Nitric acid was used to digest blister copper instead of commonly used sulfuric acid. This prevented forming the salt of copper sulfate in the filtration process when the volume of the mixture is very small. Thus, the time of filtration was saved. After filtrating, aqua regia was used to digest the residue and acidize the filter liquor. Two parts of gotten solution were directly determined by ICP-OES. The cycle of analysis was shortened compared with sulfuric acid-fire assay. The proposed method was successfully applied to determine gold and silver in blister copper, and the results were in good agreement with those obtained by lead fire assay.

MINISINI B., NEDOPEKIN O.V., PETROVA A.V., TAYURSKII D.A. — 2014 г.

Employing density functional theory (DFT) within the generalized gradient approximation, the GdLiF4 structure has been studied for a pressure range from 0 to 12 GPa. The influence of pressure on the lattice vibrational spectrum of the scheelite phase (I41/a, Z = 4) has been evaluated by means of the “direct” approach, i.e., using force constants calculated from atomic displacements. As a result, the Raman and infrared modes have been identified and their dependencies on pressure have been investigated and compared with available experimental data. It has been found that instability of the crystal structure appears at pressures above 6 GPa.

GUANG WAN, GUOQING OUYANG, QUN MA, XINYUAN SHI, YANJIANG QIAO, ZHISHENG WU — 2014 г.

The previous study mainly focused on the interpretation of the relationship between absorption characteristics and quantitative contribution in each near-infrared (NIR) frequency range. Furthermore, the absorption characteristics of NIR mainly cover overtones and combinations of molecular vibrations such as CH, OH, SH and NH bonds. And it has been know that NIR wavelengths of C-H bond and O-H bond are assigned to different radio frequencies. This paper was intended to investigate the absorption characteristics of bond C-H and O-H bonds in NIR spectral range. Water and acetone which correspond to O-H and C-H bonds have been selected as typical solvents, as well as solutes. Calibration models were established using partial least square regression (PLS) and multiple linear regression (MLR). The parameters of the model were optimized by different spectral pretreatment methods. The result showed that the model set by Savitzky-Golay smooth (SG) in the spectral region of 810–1100 nm could successfully make accurate predictions. Short wave-NIR region has been discovered as optimum characteristic absorption of C-H and O-H bonds.

GANEEV R.A. — 2014 г.

The studies of coherence properties of the harmonics generating in laser-produced plasmas, the analysis of the optical nonlinearities of deoxyribonucleic acid components, the resonance enhancement of harmonic in the cases of excitation of indium plasma by multi- and few-cycle pulses, and the application of nanoparticle-based emitters of harmonics using high-pulse repetition rate lasers are reviewed. The analysis of various aspects of plasma harmonic generation at the conditions of optimal excitation of the ablated targets irradiating by 1 kHz lasers is presented. The growth of plasma harmonic conversion efficiency, single harmonic emission, nonlinear spectroscopy of complex organic components, as well as high coherency of harmonic radiation show the advantages of using plasma harmonic technique for optimization of the sources of coherent extreme ultraviolet radiation and for the material science studies. These studies allowed a significant growth of the average power of harmonics compared with the case of 10 Hz lasers.

YAO YI, ZHAO LING, ZHAO YANG, ZHENG QUAN — 2014 г.

It is reported the efficient compact deep-blue laser at 457nm generation by intracavity frequency doubling of a continuous wave (CW) laser operation of a diode-pumped YVO4 : Nd laser on the 4F3/2 4I9/2 transition at 914 nm. An LBO crystal, cut for critical type I phase matching at room temperature is used for second harmonic generation (SHG) of the laser. With dual end pump configurations at total incident pump power of 60 W, as high as 21.8 W of CW output power at 457 nm is achieved with 20-mm-long LBO. The optical-to-optical conversion efficiency is up to 36.3%, and the power stability in 8h is better than 2.36%.

PING Y.X., SONG P., WANG L.L., YAO Y., ZHANG C.M., ZHAO L., ZHU P.F. — 2014 г.

A laser diode side pump all-solid-state pulse laser at 589 nm with high power and high conversion efficiency and small volume is demonstrated by intracavity sum frequency generation. By optimizing the cavity and adopting etalon techniques, a quasi continuous wave at 589 nm laser source, which has a maximum output power of 11.4 W, a repetition rate of 5 KHz, and a pulse width of 135 ns, is developed. The optical to optical conversion efficiency is up to 6.5% and the power stability is better than 2% in 8 hours.

BAIBEKOV E.I., BARBARA B., KURKIN I.N., MALKIN B.Z., RODIONOV A.A., ZVEREV D.G. — 2014 г.

We study paramagnetic resonance linewidth in a series of CaWO4 and CaMoO4 crystals with different concentrations of neodymium ions (0.0031–0.81 at. %). Experimental data are interpreted in the framework of the statistical theory of line broadening by charged point defects. In our calculations, three different contributions are singled out: arising from the local electric fields, electric field gradients and magnetic fields of the nearby point defects. The interaction parameters are determined from the spectroscopic data available for Nd : CaWO4 crystal. Direct calculations of the linewidth are performed for different crystal orientations with respect to external magnetic field. We conclude that major contribution to the broadening comes from the interactions with random electric fields produced by neodymium and charge compensator ions.

DU P., GENG D., GONG M., WANG T., WANG W. — 2014 г.

Because the light intensity distribution (LID) reflected by a spherical cube corner retroreflector array (SCCRA) is of great significance for the detection of the remote laser ranging to receive laser pulse echo precisely and to accomplish the function outstandingly, it is vital to find a method to calculate the LID reflected by SCCRAs with different structural parameters for the SCCRA design. Besides, considering that the reflected light goes through a complex optical system (COS) described by ABCD matrix before it reaches the detector, the method to calculate the LID should be suitable for the COS. This article derives formulae to calculate LID reflected by a SCCRA based on the lens-system diffraction formula of S.A. Collins. In the process of deriving, coordinate transformation matrixes and vector formulations are applied and the dihedral offsets are taken into account. Because the structural parameters of the SCCRA and the expression of the ABCD matrix of the COS are not limited in the deriving process, these formulae are suitable for calculation of the LID reflected by different SCCRA and going through different COS. In addition, computer simulations are applied to explain clearly how to get the LID of a SCCRA by the formulae derived in this paper.

PUKHOV K.K., SEKATSKII S.K. — 2014 г.

Cooperative fluorescence resonance energy transfer effect is experimentally demonstrated for a few crystals doped with rare-earth ions. We show that, at the liquid helium temperatures in similar crystals, coherent cooperative fluorescence resonance energy transfer, as well as an inverse coherent up-conversion process, could be observed, and briefly discuss possible applications of these effects.

HONG-DA SUN, MIAO LU, SHENG-FENG DENG, YA-QIN CHENG, ZHAO WU — 2014 г.

A compact dispersive device for Raman spectrometer was proposed to achieve a spectrum resolution below 0.55 nm in the spectral range of 800 to 1000 nm. A 41-channel arrayed waveguide grating (AWG) with eleven different diffraction orders was designed, and each output channel of this AWG contained eleven light signals with periodically 20 nm spaced wavelength. These signals were further cross-dispersed by a prism, and finally form a 41 ? 11 spots array on a CCD. The detailed theoretical analysis and simulation of this dispersive device were introduced in this paper. Compared with commercial dispersive modules composed of grating, lens and mirrors, the proposed structure is able to provide a compact device with higher spectrum resolution, which is attractive for handheld Raman spectrometer.

AHMET ERDONMEZ, GOKHAN ALPASLAN, HAKAN KARGILI, MUSTAFA MACIT, ORHAN BUYUKGUNGOR — 2014 г.

The Schiff base (Z)-1-[(2,4-dimethoxyphenylamino)methylene]naphthalen-2(1H)-one was synthesized from the reaction of 2-hydroxy-1-naphthaldehyde with 2,4-dimethoxyaniline. The title compound has been characterized by FT-IR, UV–Vis and, X-ray single-crystal techniques. The present X-ray investigation shows that the compound exists in the keto-amine tautomeric form. Molecular geometry and vibrational frequencies of the compound in the ground state have been calculated using the density functional theory (DFT) with 6-311G(d,p) basis set and compared with the experimental data. The calculated results show that the optimized geometry is compatible with the crystal structure and the theoretical vibrational frequencies are in good agreement with the experimental values. Besides, molecular electrostatic potential (MEP), frontier molecular orbital analysis (HOMO-LUMO) and non-linear optical (NLO) properties of the compound were investigated using the same theoretical calculations.

КАМАНИНА Н.В., КУЖАКОВ П.В. — 2014 г.

Рассмотрено влияние поверхностного структурирования углеродными нанотрубками ряда оптических материалов ИК диапазона спектра (бромида калия, хлорида натрия и фторида магния) на спектральные характеристики и гидрофобность.

DZHAGAROV B.M., JARNIKOVA E.S., PARKHATS M.V., STASHEUSKI A.S. — 2014 г.

The rate constants (kr) for singlet oxygen O2 (a1 g) luminescence in several selected solvents and in a binary solvent mixture (acetone–toluene) were measured. All the data have been normalized such that k = 1.0 in toluene. It has been demonstrated that the changes in these rate constants were caused both by optical properties of a medium (the local field factor and density of photon states), and by an inherent property of the emitter of 1O2 (the square of the transition moment). In its turn, the value of the transition moment is directly proportional to molecular polarizability of the medium molecules.

BADOGLU S., YURDAKUL S. — 2014 г.

by using the combination of density functional theory (DFT) B3LYP/6-311++G(d,p) within polarized continuum (PCM) model, solvent effects of 3-hydroxy-2-quinoxalinecarboxylic acid (3HQC) tautomers were investigated. Geometrical parameters, vibrational frequencies, electronic and energetic properties, and the nucleus-independent chemical shifts (NICS) were calculated in benzene, diethyl ether, and water. It has been seen that these molecular features of 3HQC are mostly solvent dependent.

GUODONG TANG, RONGQING LI, SHANSHAN KOU, TINGLING TANG, YIWEI WANG, YU ZHANG — 2014 г.

Ruthenium polypyridined-derivative complexes are used in dye-sensitized solar cell (DSSC) as a light to current conversion sensitizer. In order to lower the cost of the DSSC, the normal transition metals were used to replace the noble metal ruthenium, and some compounds [ML2L] (M = Pt, Fe, Ni, Zn; L = isonicotinic acid, L = maleonitriledithiolate, I = PtL2L, II = FeL2L, III = NiL2L, IV = ZnL2L) were selected as the replacement. The geometries, electronic structures and optical absorption spectra of these compounds have been studied by using density functional theory (DFT) calculation at the B3LYP/LANL2DZ, B3P86/LANL2DZ, B3LYR/GEN level of theory. All the geometric parameters are close to the experimental values. The HOMOs are mainly on the maleonitriledithiolate groups mixed with fewer characters of the metal atom, the LUMOs are mainly on the two pyridine ligands. This means that the electron transition is attributed to the LLCT. The maximum absorptions of complexes are found to be at 351 nm, 806 nm for compound I and 542 nm for compound II. The maximum absorptions of complexes are found to be at 884 nm for compound III, and 560 nm for compound IV. This means that those compounds may be as a suitable sensitizer for solar energy conversion applications.

XIAOCHUN ZHOU, XIAOJUN WANG — 2014 г.

Using cationic surfactant cetyltrimethylammonium bromide (CTAB) and anionic surfactant sodium dodecylbenzene sulfonate (SDBS), respectively, YVO4: Bi, Eu3+ red phosphors were prepared by a facile reaction chemistry method and their morphology, structure and luminescent properties were investigated by scanning electron microscope (SEM), X-ray diffraction (XRD) and fluorescence spectrometer. The results showed that the introduction of cationic and anionic surfactants not only greatly influenced their morphology, but induced a remarkable change XRD patterns. The reason that causes the variation of these properties for YVO4: Bi, Eu3+ red phosphors was concluded to be related to different surfactants.

RAFIZADEH S. — 2014 г.

Titanium dioxide films of different thicknesses, ranging from 10 to 110 nm were deposited on glass substrate, at room temperature by physical vapor deposition method. Topography, roughness and crystallography of produced layers were determined by AFM and XRD methods respectively. Optical properties were measured by transmission spectroscopy in the spectral range of 300–1100 nm wave length range. The optical constants were obtained using Kramers-Kronig analysis of the reflectivity curves. It was found that film thickness plays an important role on the nanostructures as well as optical properties of layers and cause significant variations in behavior of thin titanium oxide films.

MISHRA D.K. — 2014 г.

Recently we studied the test of Bell-type inequalities with superposition of two coherent states ( /2 out of phase) [D. K. Mishra, Acta Phys. Pol. A. 123, 21 (2013)]. Here, we study the effect of thermal environment on the Bell-CHSH inequality. As the state interacts with the thermal environment, the time evolution of the linear entropy to study the purity loss in the state has also been examined.

AMANULLAH FATEHMULLA, ASLAM FAROOQ W., ASLAM M., ATIF M., SYED MANSOOR ALI — 2014 г.

TiO2 thin film has been widely used as photoelectrode in dye sensitized solar cells. It can also be used in quantum dots synthesized solar cells. Study of its effects in different spectrum of light is important for its use in solar cells. We have reported effects of 1064 nm laser on the surface morphology, structural and optical properties of nanostructured TiO2 thin film deposited on glass substrates using sol gel spin coating technique. Q-switched Nd : YAG pulsed laser at various power densities is used in this study. Surface morphology of the film is investigated using X-ray diffraction and atomic force microscopy technique. The XRD pattern of as deposited TiO2 thin film is amorphous and after laser exposure it became TiO2 anatase structure. Atomic force microscopy of the crystalline TiO2 thin film shows that the grain size increases by increasing laser power density. The calculations of the band gap are carried out from UV/Visible spectroscopy measurements with JASCO spectrometer. For laser power density of 25 MJ/cm2 there is an increase in the transmission and it decreases at the value of 38 MJ/cm2 and band gap decreases with increasing laser power density. Photoluminescence spectra of the crystalline TiO2 thin film indicate two broad peaks in the range of 415 and 463 nm, one for band gap peak (415 nm) and other for oxygen defect during film deposition process.

ATUCHIN V.V., KOCHUBEY V.A., KRUCHININ V.N., POKROVSKY L.D., RAMANA C.V. — 2014 г.

The optical properties of the highly-textured V2O5 thin films grown on Si(100) by sputter-deposition at various oxygen reactive pressures were investigated in detail. The profiles of the optical constants, namely the refractive index and extinction coefficient, of V2O5 films were evaluated in the photon-energy range of 1–5 eV. At photon-energy above 2.5 eV, the dispersion behavior in optical constants is explained based on Lorentz-Drude model. The refractive index dispersion fits to a Cauchys relation at photon-energy below 2.5 eV, where the V2O5-film is mostly transparent. The optical transitions across the bandgap occur at energy 2.5 3.2 eV depending on the V2O5 growth conditions and film-microstructure. The highly-textured and c-axis oriented V2O5-films, fabricated under optimum conditions of temperature and oxygen partial pressure, exhibit excellent optical characteristics similar to V2O5 single crystals.