[en] Anti-adhesive coatings based on Zr nitrides and oxides deposited form the vacuum-arc plasma were developed. Laboratory tests that determine tribotechnical properties were conducted. Proved, that coatings based on nitrides and carbides increase the anti-adhesive properties (paper)

[en] Using MCVD, we have produced optically active fibers with a glass-ceramic core containing mullite, 3Al₂O₃ · 2SiO₂, as a major crystalline phase. Thermodynamic prediction of mullite formation conditions has been supplemented by thermal analysis and X-ray diffraction characterization of preform core samples, and fiber heat treatment (annealing) conditions have been established. Luminescence measurements for the fibers annealed under optimal conditions demonstrate that optically active chromium has a crystalline local environment.

[en] Double-clad Er-doped fibers highly doped with aluminum (up to 3 mol.%) and fluorine (up to 1.5 wt.%) have been fabricated and studied. The fibers have a core numerical aperture of approximately 0.055, which allowed us to achieve a single-mode propagation regime for a fiber core diameter of 35 µm. The possibility of increasing the pump-to-signal conversion efficiency in the L-band using the developed double-clad Er-doped fibers was demonstrated. Utilization of the F–GeO₂–Al₂O₃–SiO₂–Er fiber together with a P₂O₅–Al₂O₃–SiO₂–Er fiber was found to be promising for single-frequency amplifiers because the fibers have negligible overlap of the stimulated Brillouin scattering gain. This feature allowed us to build a cascaded double-clad Er-doped fiber amplifier (two Er-doped fibers of different types were spliced one by one) with a threshold of stimulated Brillouin scattering greater than that of an amplifier based on a single Er-doped fiber with the same net length and pump-to-signal conversion efficiency. (letter)

[en] Single-mode Er–Yb fibers with the core based on a phosphorosilicate glass matrix (up to 6.5 mol.% P₂O₅) highly doped with fluorine (up to 0.9 wt.%) were fabricated using an all-gas-phase modified chemical vapor deposition method. The core numerical aperture was in the range of 0.07–0.08 relative to the pure silica, which allowed us to increase the single-mode core diameter up to 20 μm. The slope efficiency in lasers based on the fabricated fibers reached 34% relative to the launched pump power. (letter)