Luminescence features of Ho3+ , Er3+ and Tm3+ ions in red lead added non-conventional antimony oxide glass system.

In this study, a glass system based on heavy metal oxides, namely Pb3 O4 -Sb2 O3 -SiO2 , was prepared with Ho2 O3 , Er2 O3 , and Tm2 O3 as dopants. The prepared glass were characterized using X-ray diffraction (XRD) and infrared (IR) studies. The luminescence efficiencies of the three rare earth ions viz., Ho3+ , Er3+ , and Tm3+ in the glass system were investigated, specifically focusing on green (Ho3+ , Er3+ ), blue (Tm3+ ), and near-infrared (NIR) emissions. The optical absorption (OA) and photoluminescence (PL) spectra of RE mixed glass displayed strong bands in the visible and NIR regions, which were analyzed using the Judd-Ofelt (J-O) theory. The J-O coefficients (Ωλ ) were found to be in the order of Ω2 > Ω4 > Ω6 for all the three glass. Notably, the Tm3+ -doped glass exhibited the lowest Ω2 value, which was attributed to a larger degree of disorder in the glass network due to lower fractions of Sb5+ and Pb4+ ions that take part in the glass network forming. This conclusion was arrived based on the IR studies. Furthermore, the quantitative analysis of PL spectra and decay curves indicated that SbHo and SbEr glass were suitable for efficient green emission, while SbTm glass is a promising choice for blue laser emission.

Amplification of blue emission of Tm3+ ions in Li2 O-HfO2 -SiO2 glass system by means of Au0 metallic particles.

Li2 O-HfO2 -SiO2 -Tm2 O3 :Au2 O3 glass samples (containing fixed content of Tm2 O3 and different concentration of Au2 O3 ) were prepared and characterized. Bearing of Au0 metallic particles (MPs) on improving blue emission of thulium ions (Tm3+ ) ions was explored. Optical absorption (OA) spectra exhibited multiple bands excited from 3 H6 of Tm3+ . Additionally, a broad peak in the wavelength range 500-600 nm due to surface plasmon resonance (SPR) of Au0 MPs was noticed in the spectra. Photoluminescence (PL) spectra (of thulium free glasses) indicated a peak in the visible range due to sp → d electronic transition of Au0 MPs. Luminescence spectra of Tm3+ and Au2 O3 co-doped glasses exhibited intense blue emission with substantial increase of intensity with increase of Au2 O3 content. Bearing of Au0 MPs on the reinforcement of blue emission of Tm3+ was discussed in detail with kinetic rate equations.

Influence of nanosized defects on photoluminescence efficiency of Er3+ ions co-doped with Au2 O3 in a lead boroselenate glass ceramic system: a novel approach using positron annihilation lifetime spectroscopy.

This study consists of the results of an investigation into the influence of the free-volume space (fv ) defects on luminescence efficiency (LE) of erbium ions in Au2 O3 -doped PbO-B2 O3 -SeO2 (PBS) glass ceramics. Glass ceramics containing fixed concentrations of Er3+ ions and varied concentrations of Au2 O3 were synthesized. X-ray diffraction studies indicated that the samples contained Au2 (SeO3 )3 crystalline phase and nano gold metallic particles. The concentration of defects entrenched in the glass ceramics estimated in terms of Au2 O3 content using positron annihilation lifetime spectroscopy measurement indicated the highest content in the glass ceramic containing 0.075 mol% of Au2 O3 . Optical absorption and the photoluminescence (PL) spectra of the glass ceramics were studied in the visible region. The observed increase of PL efficiency was attributed to the enhanced concentration of free-volume imperfections in the samples. A perfect correlation could be achieved between the free-volume fraction and the PL efficiency of erbium ions in these glass ceramics.