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The special attention has been paid to visualization and monitoring of harmful radiation to quantify the radiation intensity and prevent the undesired exposition. For these purposes, so called radioluminescent materials are widely exploited. Special attention has been paid to the research of luminescence optical fibers, which can be used for a construction of distributed optical sensors. We present a versatile nanoparticle doping approach to Zn2+-doped silica optical fibers. Zinc oxide nanoparticles were applied into porous silica frit by a nanoparticle-doping method providing a preform which was drawn into an optical fiber. The maximum concentration of Zn2+ ions in the fiber was 0.78 at. % causing the refractive index reached the value of 1.459. The fiber outer diameter was 124.8 μm and the fiber core diameter was 14.9 μm matching the standard telecommunication dimension. The fibers exhibited a blue radioluminescence showing the emission maximum at 395 nm. The fiber properties make them worthy of investigation as sensing elements of distributed sensors of high energy radiation.

The presented overview deals with the study of the luminescence properties of lanthanide ions incorporated into different dielectric crystalline materials for use in photonics and optoelectronics. From the crystalline materials, non-centrosymmetric hexagonal crystals of LiNbO3, Al2O3 and ZnO, together with the centrosymmetric cubic crystal of diamond, were chosen. The above-mentioned materials represent a certain cross-section through various crystal structure geometries with different internal bonding of atoms which represent different crystal vicinity for the incorporated Er ions. During more than ten years of our research, each of the crystals was doped with erbium ions and the resulting structural and luminescence properties were studied in detail and compared between the mentioned crystalline materials to find similar behaviour for erbium ions in the different crystalline materials. To better understand the incorporation of erbium in the studied crystalline materials, theoretical simulations of different erbium-doped crystal models were carried out. In the calculations, cohesive energies of the structures and erbium defect-formation energies were compared in order to find the most favourable erbium positions in the crystals. Also, from the geometry optimization calculations, the optimal geometry arrangements in the vicinity of erbium ions in different crystals were studied and visualized. The results of the theoretical simulations confirmed the experimental results – i.e., from all the theoretical erbium-doped crystal models, the most stable structures contained erbium in the substitutional positions with octahedral oxygen coordination. [ABSTRACT FROM AUTHOR]

Ion implantation of metal ions, followed by annealing, can be used for the formation of buried layers of metal nanoparticles in glasses. Thus, photonic structures with nonlinear optical properties can be formed. In this study, three samples of silica glasses were implanted with Cu+, Ag+, or Au+ ions under the same conditions (energy 330 keV and fluence 1×1016 ions/cm2), and compared to three identical silica glass samples that were subsequently coimplanted with oxygen at the same depth. All the implanted glasses were annealed at 600 °C for 1 h, which leads to the formation of metal nanoparticles. The depth profiles of Cu, Ag, and Au were measured by Rutherford backscattering and by secondary ion mass spectrometry and the results are compared and discussed. [ABSTRACT FROM AUTHOR]

We report about design, fabrication and properties of flexible polymer optical planar waveguides made of epoxy novolah resin as planar waveguides deposited on various foil substrates. The design of the presented planar waveguides was realized on the bases of modified dispersion equation and was schemed for 633 nm, 850 nm, 1310 nm and 1550 nm wavelength. Propagation optical loss measurements were done by the fibre probe technique at wavelength 633 nm (He-Ne laser) and samples have optical losses lower than 2 dB⋅cm-1. Unlike the up-to-now presented structures our construction is fully flexible what makes it possible to be used in innovative photonics structures. [ABSTRACT FROM AUTHOR]

We report about design, fabrication and properties of the polymer optical waveguides deposited on silica-on-silicon substrate. The design of the waveguides is based on a concept that geometric dimensions of the single mode polymer waveguide are determined by geometrical parameters of the silica layer. The design of the waveguides was schemed for 650 nm, 850 nm, 1310 nm and 1550 nm wavelength. The design of the presented planar waveguides was realized on the bases of modified dispersion equation while the ridge waveguides design was proposed following the Fischbeck concept. Both designs were refined applying RSoft software using beam propagation method. Proposed shapes of the waveguides were etched by standard photolithography process into the silica layers and polymer waveguide layers were subsequently deposited into the treated substrate by spin coating. Poly(methylmethacrylimide) was used as the waveguide core material and polymethylmethacrylate was used as a cover protection layer. Propagation optical loss measurements were done by using the cut-back method and the best samples had optical losses lower than 0.6 dB/cm at 650 nm, 1310 nm and 1550 nm. [ABSTRACT FROM AUTHOR]