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1.
D. Sugak A. Durygin A. Matkovskii A. Suchocki I. Solskii D. Savitskii Ya. Zhydachevskii F. Wallrafen K. Kopczynski 《Crystal Research and Technology》2001,36(11):1223-1229
The results on optical absorption, photoluminescence and thermoluminescence of YAP‐Tm crystals of 1 at.% and 4 at.% of Tm are presented as well as influence of UV‐, γ‐radiation and thermal treatments on optical and luminescence properties of the crystals. The blue‐green luminescence of defect centers was observed in YAP‐Tm crystals at Ar+‐laser excitation. The possibility of energy transfer processes between defect centers and Tm3+ ions was shown. 相似文献
2.
O.A. Buryy D.Y. Sugak S.B. Ubizskii I.I. Izhnin M.M. Vakiv I.M. Solskii 《Applied physics. B, Lasers and optics》2007,88(3):433-442
The thulium microlasers based on yttrium-aluminium perovskite and yttrium-aluminium garnet crystals are considered as coherent
light sources at the wavelength near 2 μm. The comparative analysis of these lasers is carried out by means of the lasers’
parameters optimization for each value of the pumping power taking into consideration the cross-relaxation and up-conversion
processes as well as heating of the active medium. The optimal values of the active medium length, activator concentration
and the output mirror reflectivity are determined both for Tm:YAP- and Tm:YAG-laser. The pulse generation of Tm:YAP- and Tm:YAG-lasers
is also considered, the parameters of this regime are determined. The comparison shows the suitability of Tm:YAP laser crystal
both for cw and pulse generation. The up-conversion influence on the laser characteristics is also analyzed.
PACS 42.60.Gd 相似文献
3.
A. V. Yatsenko S. V. Yevdokimov A. S. Pritulenko D. Yu. Sugak I. M. Solskii 《Physics of the Solid State》2012,54(11):2231-2235
The temperature dependence of the electrical conductivity and pyroelectric coefficient of lithium niobate crystals reduced in a hydrogen atmosphere has been studied. It has been established that the activation energy of dark electrical conduction in these crystals in the temperature range 288?C350 K differs from the corresponding values for crystals reduced in vacuum and is equal to 0.68 ± 0.02 eV. It has been shown that the annealing of LiNbO3 crystals in a hydrogen atmosphere hardly affects their pyroelectric properties. The mechanism of electrical conduction of LiNbO3 crystals reduced in a hydrogen-containing atmosphere has been discussed. 相似文献
4.
Ya. Zakharko A. Luchechko I. Syvorotka G. Stryganyuk I. Solskii 《Radiation measurements》2010,45(3-6):429-431
Optical absorption, excitation and emission spectra, as well as photoluminescence decay time of CaMoO4 single crystals have been measured. It has been revealed that annealing of crystals in oxygen atmosphere leads to the disappearance of their anisotropic behavior in optical absorption, as well as in X-ray luminescence and decay time. Moreover, it has been found that annealing can significantly affect the value of the decay time. The relative intensity of the long-wavelength emission band increases under excitation in the region of indirect band-to-band transitions. 相似文献
5.
A.S. Andrushchak B.G. Mytsyk N.M. Demyanyshyn M.V. Kaidan O.V. Yurkevych I.M. Solskii A.V. Kityk W. Schranz 《Optics and Lasers in Engineering》2009,47(1):31-38
The paper presents a technique suitable for the determination of linear electro-optic effect (LEOE) tensor components in crystal materials of any symmetry. The method is based on the Michelson interferometer, where the sample being studied is set into one of its arms to measure the electro-induced changes of the optical path. We describe in detail the sample geometries that are needed to determine a complete set of the LEOE tensor components and derive the corresponding equations. The experimental technique has been tested and verified on lithium niobate crystals as well as applied to MgO-doped LiNbO3 crystals to study their electro-optic properties. The developed method can be useful for optical engineering, which deals with new materials being used in design or production of devices, such as, e.g., modulators or deflectors. 相似文献
6.
D.I. Savytskii A.O. Matkovskii I.M. Solskii F. Wallrafen A. Suchocki L.O. Vasylechko S.B. Ubizskii 《Crystal Research and Technology》2000,35(2):197-205
The dislocations existing in single crystals of neodymium gallate and yttrium aluminate grown by the Czochralski technique have been studied by means of etch pits. The data concerning their solubility in cases of different directions of a face orientation, various treatment temperatures and several enchant types are reported. The investigation of etch pits in the twinned YAlO3 and NdGaO3 crystals showed that twins are formed during a growth process. In the [110]‐pulled NdGaO3 crystals the discrepancy between the twin and matrix parts of a crystal is accommodated by the dislocation congestion and the dislocation low‐angle boundaries whereas in [010]‐pulled YAlO3 crystals the microcracks perform this function. 相似文献
7.
P. Potera S. Ubizskii YA. Zhydachevskii D. Sugak Solskii T. Lukasiewicz 《辐射效应与固体损伤》2013,168(12):821-824
The present work is devoted to investigation of optical absorption in pure and neodymium-doped YAlO3 (YAP) single crystals in the spectral range 0.2–1.1 μm induced by the influence of 12C ions irradiation with energy 4.50 MeV/u (MeV per nucleon) and a fluence 2 × 109 cm?2 or of 235U ion irradiation with energy 9.35 MeV/u and a fluence 5 × 1011 cm?2. The induced absorption in the case of 12C ions irradiation is caused by recharging of point growth defects and impurities under the radiation influence. After irradiation by 235U ions with fluence 5 × 1011 cm?2 the strong absorption rise is probably caused by contribution of the lattice destruction as a result of heavy ion bombardment. 相似文献
8.
V. Yakovyna A. Matkovskii D. Sugak I. Solskii S. Novosad 《Radiation measurements》2004,38(4-6):403-406
The influence of annealing in different atmospheres on absorption and luminescent properties of high-quality undoped CaWO4 single crystals is presented. The decreasing of green emission intensity after annealing in oxygen and air have been revealed, while two well-defined maxima near 25,000 and 32,000 cm−1 can be observed in the induced absorption spectra. These maxima are attributed to the interstitial oxygen, possibly in the form of the O−-centre. The increase of the blue/green luminescence ratio has been revealed after annealing in nitrogen while the crystal transparency remains unaffected. The possible ways to reduce slow green emission component without changing crystal absorption are shown. Structure of colour centres and the models of revealed processes are discussed. 相似文献
9.
S. S. Novosad L. V. Kostyk I. S. Novosad I. M. Solskii 《Journal of Applied Spectroscopy》2010,77(5):728-731
We have studied thermally and photostimulated recombination processes in PbWO4 crystals in the temperature interval 90–295 K. We have shown that after x-ray excitation of the crystal at 90 K, the thermally
stimulated luminescence curve shows a relatively intense peak at 110 K and weak peaks at about 173, 191, and 232 K. Exposure
of the PbWO4 crystal to IR radiation after excitation by x-ray photons leads to the appearance of photostimulated flash luminescence,
a significant decrease in the intensity of the 110 K peak, and a shift of that peak to the 116 K region. But long-wavelength
illumination has less of an effect on the intensity and position of the higher temperature peaks. It is assumed that F− centers are formed in the PbWO4 crystal at 90 K during x-ray exposure. The thermal light sum released by IR illumination in the temperature region 90–150
K has a maximum at ≈108 K. The nature of this maximum is connected with the complex centers [Pb3+ + (WO3-F−)]. Optical and thermal degradation of these centers leads to the appearance of emission in the green region of the localized
exciton spectrum. 相似文献
10.
N. Krutyak R. Gladyshevskii Z. Moroz S. Mudry M. Pashkovskii I. Solskii 《Radiation measurements》2004,38(4-6):563-566
The influence of doping (with F, Gd and Mo ions) and co-doping (with F, Gd or F, Gd, Mo ions) of PbWO4 crystals was investigated. It is shown that even a small amount of specific impurities (especially F ions) causes an important redistribution of the point defects and changes the physical properties of the crystals. The cell parameters were refined from X-ray powder diffraction data. It was found that the cell parameters of F-doped PbWO4 samples are larger than those of undoped samples. Photoluminescence and optical transmission spectra of pure and doped PbWO4 were investigated. 相似文献