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Bi Dongxue Sverbil Pavel P. Voinov Yury P. Wu Mengyuan 《Journal of Russian Laser Research》2021,42(6):671-676
Journal of Russian Laser Research - We discuss the use of high-pressure high-temperature (HPHT) diamonds for the determination of trace amounts of various Raman active substances. The amount of the... 相似文献
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Secondary radiation (photoluminescence and Raman scattering) emitted by gallium phosphide single crystals at helium temperatures is investigated. It is established for the first time that, in the case when the secondary emission spectra are excited by a cw low-power He-Ne laser, whose linewidth lies in the transparency region of GaP, anti-Stokes photoluminescence from the bulk of the sample occurs due to interband and impurity recombination. The results obtained make it possible to carry out a qualitative and quantitative analysis of impurities which are present in the bulk of a semiconductor by recording the bulk anti-Stokes photoluminescence spectra at low temperatures. 相似文献
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V. S. Gorelik A. A. Esakov A. N. Morozov P. P. Sverbil’ S. D. Tyves 《Journal of Russian Laser Research》2008,29(1):71-89
We developed a method for detecting traces of foreign components in water and analyzing the microstructure of water. The method
is based on studies of the characteristics of secondary emission arising in aqueous media under excitation by radiation of
ultraviolet lasers and light emitting diodes. A new type of cuvette (capillary cuvettes) for studying the secondary emission
in molecular media was elaborated. The cuvettes enable the study of aqueous solutions at small concentrations of the components;
they enable one to recognize the type of molecular compound present in aqueous media, in view of the photoluminescence spectra. 相似文献
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Yu.?P.?Vo?nov N.?F.?Gabitova V.?S.?Gorelik L.?I.?Zlobina P.?P.?Sverbil’ 《Physics of the Solid State》2009,51(7):1409-1413
This paper reports on a comparison of transmission, reflection, and secondary radiation spectra of unloaded synthetic opals and samples filled with the sodium nitrite ferroelectric (NaNO2). The radiation is provided by semiconductor light-emitting diodes operating in the ultraviolet and visible spectral regions. Selective excitation of slow electromagnetic waves in a photonic crystal, an effect observed when the exciting radiation frequency approaches the stop-band edge, is studied. 相似文献
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V. M. Buznik V. S. Gorelik P. P. Sverbil’ A. K. Tsvetnikov A. V. Chervyakov 《Physics of the Solid State》2002,44(12):2331-2335
The Raman spectra of ultrafine powders consisting of F(CF2)nF fluoropolymer zigzag molecules treated as a one-dimensional nanocrystal are investigated. These spectra are compared with the Raman spectra of CnF2n+1Br compounds (n=6–10 and 14) and fluoroplastics. It is found that the frequencies of optical vibrations of F(CF2)nF fluoropolymer molecules are shifted by more than 10 cm?1 with respect to the relevant frequencies of C6F13Br molecules. The length of nanoparticles comprising an organofluoric ultrafine powder is estimated to be L=2–2.5 nm. This estimate is obtained from the measured frequency shifts in terms of the vibrational theory for a crystalline diatomic chain of finite length. 相似文献
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V. S. Gorelik L. I. Zlobina P. P. Sverbil’ A. A. Vedernikov Yu. P. Voinov 《Bulletin of the Lebedev Physics Institute》2016,43(3):93-97
Secondary emission spectra of globular silica photonic crystals when their surfaces were exposed to laser pulses 250 fs long at a power density to 1 TW/cm2 have been studied. Optical harmonics and plasma emission were detected in this case. For the opal matrix containing pores filled with air, in the reflection mode, the third optical harmonic with a conversion efficiency of ~10% arises. The highest conversion efficiency for exciting radiation with wavelengths of 1026 or 513 nm is implemented when the frequencies of the exciting radiation or the second harmonic are near the stop band edge. In globular photonic crystals filled with sodium nitrite or barium titanate ferroelectrics, the second optical harmonic is observed. The exciting radiation conversion efficiency to the second optical harmonic was a few percent and depended on the frequency of exciting radiation and photonic crystal globule diameters. It is found that the plasma emission intensity increases with the exciting radiation power density. The dependences of the intensity of the second and third optical harmonics on the pump intensity are constructed for various photonic crystal globule diameters. 相似文献
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V. S. Gorelik P. P. Sverbil A. I. Vodchits Yu. P. Voinov 《Bulletin of the Russian Academy of Sciences: Physics》2018,82(3):257-260
Isofrequency dependences of the spectral intensities of inelastic scattering in LiTaO3, Pb5Ge3O11, BaTiO3, and KNbO3 crystals are registered at a fixed frequency of the spectrometer close to that of the exciting radiation. Results from soft mode analysis are presented. 相似文献
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V. S. Gorelik K. I. Zaitsev V. A. Lazarev S. O. Leonov S. O. Yurchenko Yu. P. Voinov L. I. Zlobina P. P. Sverbil 《Journal of Russian Laser Research》2016,37(3):254-258
We investigate the second harmonic generation under femtosecond pulse-periodic laser radiation in barium titanate in the form of ceramics, in pores of a globular photonic crystal, and in a water colloidal suspension. We measure the dependence of the second harmonic radiation intensity on the incident laser power. Excitation of the second harmonic was carried out by powerful (108 W) pulses of a solid-state Yb:KGW laser (wavelength, 1,026 nm) operating at 200 kHz. We estimate the efficiency of the second harmonic generation in various microstructured phases of barium titanate and show that the threshold of plasma formation in a suspension of barium titanate microparticles in water is substantially higher than in ceramics and in the ferroelectric photonic crystal. The second-harmonicgeneration power can be significantly increased in a water suspension of barium titanate microparticles. 相似文献