Luminescence spectra of germanosilicate optical fibres I - radioluminescence and cathodoluminescence

Data are reported on the luminescence spectra generated by X-ray and electron irradiation of optical fibres, fibre preforms and silica. The impurities and imperfections in the fibre core have a higher luminescence efficiency than those in the substrate material. The core luminescence provides a major fraction of the total light emission, despite the fact that the core is a small fraction of the total fibre volume. A wide variety of overlapping emission bands are reported. The spectra are strongly temperature dependent but the component emission bands can generally be linked to either Ge impurities, giving the 400 nm band, exciton emission near 460 nm or other blue/UV bands linked to E'-type defects. Overall, the study of the fibre luminescence provides a sensitive technique for analysis d changes and repeatability of fibre fabrication

Optical Properties and Characterization of Prepared Sn-Doped PbSe Thin Film

Physical vapor deposition of tin-doped lead selenide (Sn/PbSe) thin films on SiO2 glass is described. Interaction of high-energy Ar+ ions bombardment on the doped PbSe films is discussed by XRD analysis. The improvement of optical band gap of Sn/PbSe films irradiated by different doses of irradiation was studied using transmission spectroscopy

A survey of conductivity of nanotubes indirectly doped with nitrogen using equations Kramerz-Kronig

Doping of carbon nanotubes with nitrogen should provide more control over the nanocarbon electronic structure. In addition to the chemical and arc-discharge alternative methods used nowadays, we suggest ion irradiationas an alternative way to introduce N impurities into nanotubes. The impinging ions can directly occupy the sp2 positions in the nanotube atomic network. As an alternative way N nitrogen atoms are introduced due to the same atomic radius. In this work we studied the defects caused by exposure to N2 with various energies with the Raman spectroscopy. Kramers–Kronig analysisis determined the optical conductivityof multiwall carbon nanotudes. Electrical measurements showed that conductivity of samples increases with enhancement of irradiation of MWCNTs, clearly due to creation of more defects and N-C and irradiation-mediated doping of nanotubes is a promising way to control the nanotubes electronic structure

Ion beam luminescence of Nd:YAG

No description supplie

Ion beam luminescence of thin film CdS on glass formed by pulsed laser deposition

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Cathodoluminescence of small silicon nanoparticles under electron beam excitation

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Cathodoluminescence of electron irradiated opal-based nanocomposites

Synthetic opals infilled with silicon (opal-Si) and with Si and Pt (opal-Pt-Si) have been irradiated in a scanning electron microscope under high excitation conditions. Electron irradiation-induced changes in the morphology and luminescent defect structure of both types of nanocomposites were assessed by scanning electron microscopy and by cathodoluminescence (CL) microscopy and spectroscopy. Irradiation causes strong morphological changes in the ordered structure of the matrix and quenching of the nanocrystals-related CL emission in the opal-Si samples. On the contrary, such effects are not observed in the opal-Pt-Si nanocomposites. In both types of samples, electron irradiation induces the appearance of a CL band centered at 2.95 eV, attributed to complex centers involving oxygen vacancies in the silica spheres forming the matrix