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The problem of creating three different types of spatially selective voxels by laser radiation in the volume of an transparent optical medium was solved. Each of the created voxels provides one base color: red, green, or blue. Red and green voxels are microvolumes inside a crystal in which femtosecond laser pulses create luminescence centers that emit, respectively, in the red and green regions of the spectrum when illuminated with blue radiation that excites luminescence. Voxels responsible for the blue glow are microvolumes in which light scattering centers are created by femtosecond pulses. These voxels do not contain any luminescence centers; they scatter blue radiation, which excites the luminescence of red and green voxels. To solve the problem of creating spatially separated voxels of all three types in the volume of an optical carrier, we studied the temperature dependences of the spectra, the output, and the decay time constants of the luminescence of quantum systems created by femtosecond laser radiation. These dependences were studied during heating and cooling. The change in the voxel size of the three basic colors from the energy and the number of femtosecond pulses of a titanium-sapphire laser was studied. Irradiation regimes were found in which only luminescence centers are formed in voxels and scattering centers are not formed. On the basis of the results, a three-stage technology of laser irradiation and heat treatment of optical media was proposed and experimentally tested. This technology allows for creation of three-dimensional, full-color images, visualized under blue light.

A miniature low-voltage vacuum spark is an effective facility for creating composite layers in a dielectric matrix, including metal clusters, which have numerous optical applications. The results of studies of the optical characteristics of alkali-halide crystals (LiF and KCl) irradiated with beams of accelerated metal ions, which are emitted by a small-sized, low-voltage (2.5 kV) and low-energy (10 J) vacuum spark and a high-voltage (50 kV) pulsed ion implanter are presented. In both cases, composite layers of metal nanoparticles and/or molecular clusters are formed at submicrometer depth when irradiating these crystals. The low voltage implant method produces similar optical effects as seen in crystals processes at much higher energies. This result shows the possibility of creating a desktop metal ion implanter for various applications.

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.

A new method for laser recording of three-dimensional color luminescent images in the volume of an optical carrier based on a lithium fluoride crystals. The mechanisms of spatially selective formation of pixels emitting in the red, green and blue regions of the spectrum by femtosecond laser radiation were investigated and realized.

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 possibility of the influence of thermal effects on the formation of color centers during laser femtosecond filamentation in a LiF crystal has been investigated theoretically. The conditions are formulated under which the influence of thermal effects can be noticeable.