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The temperature dependences of luminescence in slip planes (111) of diamond plates containing nitrogen defects A and B1 upon excitation by a laser with a wavelength of 532 nm were investigated with the use of confocal scanning luminescence microscopy. The red glow of the diamond in the slip planes was dominated by the glow of the center with a zero phonon line (ZPL) of 656 nm at 290 K and the glow of the center with a zero phonon line of 701 nm at 80 K (i.e., spectra were different at different temperatures).

The paper presents the results of luminescent studies of organs and tissues of endemic pelagic crustaceans during ontogenesis through the example of Epischura baikalensis. The spectral-kinetic characteristics of luminescence of E. baikalensis specimens have been measured. The results of laser confocal scanning luminescence microscopy studies with time resolution showed that the luminescence spectra of E. baikalensis is mainly defined by emission of Green Fluorescent Protein (GFP) and chlorophyll contained in cells of phytoplankton.

Color centers, found in lithium fluoride crystals grown in a reducing atmosphere and irradiated with a low dose of X-ray radiation, emit spectral luminescence band with maximum λmax = 800 nm and decay time constant of 26.5 ± 1 ns at room temperature. As the radiation dose increases, the concentration of these centers quickly saturates, while the concentrations of known intrinsic color centers continue to increase. This indicates the impurity nature of these color centers. The trajectories of the luminescence intensity and the decay time constants of single centers of this type were investigated. The luminescence is of flickering character. The temporal characteristics of the trajectories of luminescence intensity for different centers of the same type are different, while their decay time constants are the same. Similar pattern was revealed for the F2 color centers. These properties of single color centers in monocrystals are discussed.

The formation of thin layers of luminescent defects on the faces of planar lithium fluoride crystals located in the positive column and Faraday dark space of a glow gas discharge was studied by time-resolved confocal scanning luminescent microscopy and time-correlated single photon counting. The formation of aggregated color centers in the surface layers of crystals was established using the spectral and kinetic characteristics of luminescence appearing after irradiation. The role of gas discharge electrons, ions, and photons in the defect formation mechanism was considered. The defects were shown to be formed under the influence of vacuum ultraviolet (VUV) photons. The VUV radiation intensity distribution in the discharge gap was measured by the method of thermostimulated luminescence. The main source of this radiation was the anodic and cathodic voltage drop regions in a glow discharge.

The kinetic characteristics and temperature quenching of the luminescence of optical centers of silicon vacancies (SiVs) in diamond films grown in microwave plasma on substrates of aluminum nitride and synthetic diamond are investigated via laser excitation at a wavelength of 640 nm.

The microstructure of lithium fluoride thin films deposited on a glass substrate by thermal vacuum evaporation was investigated. An additional annealing of the films in air at temperatures of 400, 500, and 600°C resulted in an increase in the size of grains forming the film, as well as in the transformation of luminescence spectra of the initial and annealed samples before and after their X-ray irradiation used to generate in the films color centers that played the role of luminescent probes. It was found that an increase in the annealing temperature with an increase in the size of grains leads to a decrease in the intensity of the characteristic photoluminescence bands of color centers in lithium fluoride and to the appearance of new luminescence bands that are not characteristic of this material. Based on the results of the X-ray powder diffraction analysis, it was concluded that the increase in the grain size is caused by the change in the chemical composition of the films primarily due to the interaction of lithium fluoride with the substrate material.

The commented article contains numerous errors. The presentation of experimental data is slipshod and biased. They are not credible. The author had no reason to write about the scientific achievements outlined in the sections Abstract and Conclusion. One of the main conclusions of the work, that the author for the first time experimentally observed relation between orbital angular momentum of femtosecond laser radiation and induced by this radiation helicity of the tracks in crystals, has not been confirmed by direct check experiments. No orbital angular momentum of the exciting radiation nor the twisted tracks has been observed in the experiments. Other conclusions are also baseless.

The luminescent characteristics of the layers formed in the LiF and KCl crystals as a result of irradiation of the crystals by ions emitted by a small-sized low-voltage vacuum spark with a voltage < 2 kV and a pulse duration of about 1 µs were studied. The photoluminescence technique showed that because of the irradiation, layers of sub-nanoscaled metal clusters are formed in crystals. Optical characteristics of these layers are close to those of layers formed owing to irradiating of the crystals by an ion beam with energy up to 150 keV emitted by a high-voltage ion implanter MEVVA. The results show that this "table-top" source of high-energy beams of metallic ions accelerated by a collective mechanism can be used to create modified micron scale layers in optical crystals for various applications.

The axial VUV radiation intensity distribution (< 130 nm) of an air glow discharge at pressure 50–530 Pa was obtained by the thermoluminescent method using the CaSO4·Mn thermoluminophor. The regions of maximum intensity of VUV radiation are the near-electrode regions in a wide range of pressures and voltages. The positive column of a glow discharge is also an area of intense VUV radiation at high-voltage. The formation of thin layer of luminescent defects on the faces of planar lithium fluoride crystals located in the positive column and Faraday dark space of a glow gas discharge was studied. By using a MicroTime 200 time resolution laser confocal scanning luminescence microscope (PicoQuant Gmbh) it was shown that the highest concentration of luminescent defects corresponds to the sides of the crystals that were irradiated near the electrodes.

Luminescence kinetics in the temperature range of 80–480 K and the red region of the spectrum is studied for Brazilian diamonds. Components with decay time constants of 23 and 83 ns are observed at room temperature after being excited by laser radiation with wavelengths of 375 and 532 nm, which differs considerably from the data published earlier for the luminescence kinetics of NV0- and NV–-centers.

Plates made of diamonds from the São Luiz province (Brazil) were investigated by confocal scanning luminescence microscopy. The samples have many macroinhomogeneities (cracks and inclusions), but there is a quasi-uniform distribution of luminescence centers in the bulk. At all investigated points of the crystals, the same group of centers was observed: N3, H4, 575, and a red band with a maximum at 690–700 nm. The visible nonuniformities in the distribution of luminescence over the area of the plates are determined by relatively small fluctuations in the ratio of the intensities of individual bands in the spectra. Nitrogen centers of different degrees of aggregation (H4, N3, and 575 nm, with four, three, and one nitrogen atom, respectively) coexist in these crystals. In the same zones of the samples, the distribution of blue luminescence (N3 centers) is diffuse (uniform), but the distribution of yellow-green luminescence is characterized by layering on (111). This might be a consequence of the tangential growth of octahedron faces or a result of plastic deformation of the crystals and dislocations along (111).

Under radiation from a barrier discharge, luminescent color centers are formed in a surface layer of lithium fluoride crystal served as a dielectric barrier. Analysis of the damping kinetics and luminescence spectra has revealed these centers to be F3+ and F2 centers. Structural defects are mainly formed via the photon-induced mechanism (i.e., defects are formed due to the generation of electron-hole pairs as a result of absorption of photons of barrier-discharge radiation). Barrier discharge in different gases can be successfully used to form thin layers containing luminescence centers on the surface of transparent insulators for various scientific and practical applications.

Line-by-line two-dimensional step small-scale scanning irradiation of a transparent cubic LiF crystal was carried out by intense linearly polarized femtosecond laser radiation in the multiple filamentation mode. As a result, isolated longitudinal extended tracks consisting of induced color centers were formed in the medium. It was found that no transverse periodicity associated with the scanning step is observed in the arrangement of tracks formed by laser filaments. This is because inhomogeneities that stimulate filamentation are not contained in the laser beam itself but are formed randomly when the medium interacts with the first laser pulses and are supported and amplified by subsequent pulses. The efficiency of color center formation in crystals at normal laser beam incidence on the cube face depends periodically on the azimuth angle θ between the electric vector and the cube edge on the face, with the period of π/2. It was found that azimuthal dependences for defect formation (maximum at θ = π/4) and for carrier photogeneration (maximum at θ = 0) are in the antiphase. Calculations showed that the processes of self-focusing and filamentation controlled by the components of the third-order nonlinear susceptibility tensor are most effective at the orientation where θ = π/4. The experiment showed that at such an orientation, the critical power and the length of self-focusing decrease, and therefore, the density of the number of filaments in the beam section increases and, as a result, the average concentration of the color centers created by laser filaments increases.

The spectral properties of a promising laser material, ternary molybdate Li3Ba2Gd3(MoO4)8:Nd3+, are studied (i.e., its optical absorption spectra, luminescence spectra, kinetic of luminescence decay, and temperature dependence of luminescence). Luminescence of the crystalline matrix is detected, and the temperature dependence of its intensity and reabsorption by neodymium are investigated.

Using confocal fluorescence microscopy technique, we observed experimentally the luminescence of single F2 color centers in LiF crystal. It is disclosed that the fluorescence shows blinking behavior. It is shown that this phenomenon is caused by the F2 center reorientation occurring during the experiment. The ratio of luminescence intensities of differently oriented centers is assessed theoretically for two different experiment configurations. The calculated ratios are in fine agreement with experimental result.