0000000000185440
AUTHOR
Y. Maksimov
Luminescence of fluorine-doped and non-doped silica glass excited with an ArF laser
Abstract The role of fluorine doping on silica has been studied through comparison of the luminescence of fluorine doped and fluorine-free samples made by melting in on SiF4 atmosphere and excited by an ArF laser (6.4 eV) in the temperature range 10–290 K. The fluorine doped sample possesses a very weak absorption band at 7.6 eV on the level of 0.1 cm−1 and there the photoluminescence of so-called oxygen-deficient centers in the blue (2.7 eV) and UV bands (4.4 eV) could be excited. The same luminescence bands are observable in the fluorine-free sample, which contains an absorption band at 7.6 eV on the level of 20 cm−1. In the fluorine-doped sample the UV band prevails over the blue band. T…
Self-trapped exciton luminescence in crystalline α-quartz under two-photon laser excitation
Abstract The luminescence of pure crystalline α-quartz is studied under pulsed ArF laser excitation. The luminescence parameters obtained correspond well with those of self-trapped excitons (STEs) in α-quartz, indicating that the excitation process is two-photon. The efficiency of two-photon excitation is of the same order of magnitude as the one-photon excitation of sodium salicylate. The STE luminescence decay kinetics and their temperature dependence under photoexcitation were recorded with higher accuracy than previously. Changes in the decay kinetics with temperature are explained by the splitting of the STE triplet state in zero magnetic field and are analyzed with the assumption of t…
Luminescence of γ-radiation-induced defects in α-quartz
Optical transitions associated with γ-radiation-induced defects in crystalline α-quartz were investigated by photoluminescence excited by both pulsed synchrotron radiation and steady-state light. After a 10 MGy γ-dose we observed two emissions at 4.9 eV (ultraviolet band) and 2.7 eV (blue band) excitable in the range of the induced absorption band at 7.6 eV. These two luminescence bands show a different temperature dependence: the ultraviolet band becomes bright below 80 K; the blue band increases below 180 K, but drops down below 80 K. Both emissions decay in a timescale of a few ns under pulsed excitation, however the blue band could also be observed in slow recombination processes and it…
Luminescence of GeO2 glass, rutile-like and α-quartz-like crystals
Abstract The luminescence of GeO 2 rutile-like crystals was studied. Crystals were grown from a melt of germanium dioxide and sodium bicarbonate mixture. Luminescence of the crystal was compared with that of sodium germanate glasses produced in reduced and oxidized conditions. A luminescence band at 2.3 eV was observed under N 2 laser (337 nm). At higher excitation photon energies and X-ray excitation an additional band at 3 eV appears in luminescence. The band at 2.3 eV possesses intra-center decay time constant about 100 μs at 290 K and about 200 μs at low temperature. Analogous luminescence was obtained in reduced sodium germanate glasses. No luminescence was observed in oxidized glasses…
Recombination luminescence of oxygen-deficient centers in silica
Abstract The luminescence of silica glass, prepared by plasma chemical vapor deposition (PCVD) and quartz glass of type IV (trade mark KS-4V) methods, were studied while irradiated with pulses of ArF laser (193 nm) light in the range of sample temperatures between 10 and 300 K. The samples contain less than 0.1 ppm metallic and hydroxyl impurities. The samples synthesized by PCVD were of two kinds. The first one (amorphous) was as-deposited from plasma at a substrate tube temperature of ∼1200 °C. The second one (fused) was prepared from the first by the tube collapsing with an external burner. In this process, a section of the substrate tube with the deposited glass was installed in a lathe…