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Kolesnikov I.E.,Saint Petersburg State University | Tolstikova D.V.,Saint Petersburg State University | Kurochkin A.V.,Saint Petersburg State University | Pulkin S.A.,Saint Petersburg State University | And 2 more authors.
Journal of Luminescence | Year: 2014

Eu3+-doped YVO4 nanopowders were prepared by the modified Pechini method. The structural properties were studied with XRD, SEM and Raman spectroscopy. XRD pattern indicates that nanocrystalline YVO4:Eu3+ powders form only pure tetragonal phase. SEM images show that synthesized samples are mixture of large, well-faceted particles and weakly agglomerated nanoparticles. The symmetry of luminescent centers local surrounding was discussed in terms of asymmetry coefficient. Dependence of luminescent intensity on Eu3+ doping concentration was studied at different excitation wavelengths. Lifetimes of 5D0 level were measured for all the synthesized nanopowders. Also the probabilities of radiative, nonradiative processes, and the radiative lifetimes were calculated. ©2014 Elsevier B.V. All rights reserved. Source


Kolesnikov I.E.,Saint Petersburg State University | Tolstikova D.V.,Saint Petersburg State University | Kurochkin A.V.,Saint Petersburg State University | Manshina A.A.,Saint Petersburg State University | Mikhailov M.D.,Scientific and Technological Institute of Optical Material Science
Optical Materials | Year: 2014

Nanocrystalline Eu3+-doped YAG powders were prepared by modified Pechini method. The structural properties were investigated with XRD, SEM and Raman spectroscopy. XRD pattern indicated that the phase-pure YAG:Eu3+ crystallites were obtained without the formation of any other phases. Raman spectrum revealed good homogeneity and crystallinity of synthesized nanopowders. The luminescent properties were studied by measurement of excitation and emission spectra, quantum yields and decay curves. The effect of Eu3+ concentration on 5D0 level lifetime was studied. The processes resulting in the relaxation of excited state (5D0 level) were discussed and the probabilities of radiative and nonradiative processes were calculated using the model of f-f transition intensities. It was found that the observed shortening of 5D0 level lifetime with Eu concentration is caused by increase of nonradiative process probability. © 2014 Elsevier B.V. All rights reserved. Source


Garanin S.G.,RAS Federal Nuclear Center | Rukavishnikov N.N.,RAS Federal Nuclear Center | Dmitryuk A.V.,Scientific and Technological Institute of Optical Material Science | Zhilin A.A.,Scientific and Technological Institute of Optical Material Science | Mikhalov M.D.,Saint Petersburg State Polytechnic University
Journal of Optical Technology (A Translation of Opticheskii Zhurnal) | Year: 2010

This section of this review discusses the main features of methods for producing a new laser material-a ceramic for the development of powerful next-generation solid-state lasers. A laser ceramic with a perfect crystalline structure and containing no impurities is virtually identical to microcrystals of the same composition in its spectral and laser characteristics. The main methods of synthesizing precursors for a laser ceramic and examples of the technological implementation of these methods are considered. © 2010 Optical Society of America. Source


Kolesnikov I.E.,Saint Petersburg State University | Tolstikova D.V.,Saint Petersburg State University | Kurochkin A.V.,Saint Petersburg State University | Platonova N.V.,Saint Petersburg State University | And 3 more authors.
Materials Research Bulletin | Year: 2015

Abstract Nd3+-doped YVO4 nanophophors were prepared using modified Pechini method. Synthesized samples consist of large particles about 1 micron and weakly agglomerated nanoparticles with size about 200 nm. The effect of the doping concentration on the structure and luminescence was investigated. It was found that increase of Nd3+ concentration leads to the growth of unit cell parameters and red shift of Raman lines. Concentration dependence on the luminescence intensity was studied under different excitation wavelengths. Decay curves of 4F3/2-4I11/2 transition were observed for different doping concentration. Lifetime of excited level 4F3/2 was obtained from fitting. © 2015 Elsevier Ltd. Source

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