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In this paper, we report on fabricating optical fibers with a controlled process of crystallization core during the drawing process. The research and synthesis of the core material of silica-germanium-antimony oxide glass were discussed. We also investigated the optical and luminescence properties were in relation to concentrating Eu 2 O 3 and P 2 O 5. Based on this investigation, we selected the most promising material for optical fiber core. In the next step, we drew optical fibers using a well-known rod-in-tube method. After drawing, we examine the optical fibers for luminescence shape changes. We observed a promising similarity between optical fibers and heat-treated samples with confirmed nanocrystals. Finally, XRD and TEM measurements confirm EuPO 4 nanocrystals at the core of the optical fiber. Highlighting the successful control of crystallization in the one-step method used to draw optical fibers. [ABSTRACT FROM AUTHOR]

This work presents an analysis of the spectroscopic properties of glass and glass ceramics co-doped with Ni2+ and Er3+ ions. Spectroscopic analysis showed the embedding of nickel ions in the gamma-gallium oxide nanocrystals as a result of heat treatment of the glass samples. Analysis of the luminescence properties of the obtained samples under 940 nm and 980 nm pump excitation allowed the selection of a proper Er3+ ions concentration for further optical fiber fabrication. Measured lifetime results of glass-ceramics samples confirm energy transfer from nickel ions to erbium. In the process of drawing the optical fiber, it was possible to create a transparent nanocrystalline glass-ceramic core, as confirmed by XRD results. The produced glass-ceramic optical fiber was characterized by broadband emission in the range from 1100 nm to 1650 nm corresponding to the 3T 2 (3F) →3A 2 (3F) (Ni2+) and 4I 13/2 → 4I 15/2 (Er3+) transitions for 940 nm and 980 nm pump excitation. The Er3+ to Ni2+ ions emission intensity ratio of the fabricated glass-ceramic fiber was estimated to be 0.84 and 7.14 for 940 nm and 980 nm optical pumps, respectively. [ABSTRACT FROM AUTHOR]

Luminescent properties of silica sol–gel nanomaterials doped with Tb 3+ ions were studied and the results are presented. Compositions of the studied materials were varied while the terbium ions concentration was kept constant. Some technological parameters were analyzed and their pronounced effect on the photoluminescence properties is observed. Spectroscopic parameters of Tb 3+ ions were determined basing on excitation and emission measurements as well as on luminescence decay analysis before and after heat treatment process. The registered emission bands in the visible spectral range correspond to the 5 D 4 → 7 F J ( J =3−6) transitions of Tb 3+ ions. Intensities of the emission bands and luminescence decay curves of Tb 3+ ions depend on the excitation wavelength. Also, enhancement of the emission bands intensities and a significant increase of luminescence lifetime for the 5 D 4 excited state of Tb 3+ ions after heat treatment process was observed. The structure of obtained glasses was examined using X-ray diffraction (XRD), as well as FT-IR and Raman spectroscopic techniques. The obtained results indicate the incorporation of Tb 3+ ions into nanocrystalline phase during ceramization process. [ABSTRACT FROM AUTHOR]

Abstract: Lead borate glasses were prepared and then heat treated in order to obtain transparent glass-ceramics. Controlled crystallization of precursor lead borate glass at appropriate annealing temperature and time led to formation of the PbWO4 crystallites. The observed broad blue emission band is related to the PbWO4 crystallites. The influence of PbX2 content (X=F, Cl, Br), PbF2 concentration and lanthanide doping (Eu, Dy) on the excitation and emission spectra of lead borate glass-ceramics containing PbWO4 phase was examined. The relationship between Pb–X bond and spectral line width of the blue emission can be successfully observed, when halogen X ions (X=F, Cl or Br) are also present in the distorted PbWO4 crystallites. [Copyright &y& Elsevier]