Search

We have investigated the spectroscopic properties of Er3+-doped fluorotellurite glasses with the basic molar composition 75%TeO2-10%P2O5-10%ZnO-5%PbF2, modified by replacing 5% TeO2 by a metal oxide, namely WO3 or Nb2O5. The absorption edge of the glasses studied has been described within the Urbach approach, while the absorption and photoluminescence spectra have been analyzed in terms of the standard Judd-Ofelt theory, along with the photoluminescence decay of the 4I13/2 and 4S3/2 levels of the Er3+ ion. The absorption and emission spectra of the 4I15/2 ↔ 4I13/2 infrared transition have been analyzed within the McCumber theory to yield the peak emission cross-section and figure of merit for the amplifier gain. It appears that the fluorotellurite glass containing WO3 as a modifier is characterized by the largest figure of merit, indicating this matrix as a promising new host for doping with Er3+ ions. [ABSTRACT FROM AUTHOR]

We have investigated the optical and spectroscopic properties of new Er 3+ -doped fluorotellurite glasses with the basic molar composition 75%TeO 2 -10%P 2 O 5 -10%ZnO-5%PbF 2 , modified by replacing 5%TeO 2 by four various metal oxides, namely MgO, PbO, SrO and CdO. The ellipsometric data have provided a Sellmeier-type dispersion relation of the refractive index of the investigated glasses. The optical absorption edge has been described within the Urbach approach, while the absorption and fluorescence spectra have been analyzed in terms of the standard Judd–Ofelt theory along with the photoluminescence decay of the 4 I 13/2 and 4 S 3/2 levels of the Er 3+ ion. The absorption and emission spectra of the 4 I 15/2 ↔ 4 I 13/2 infrared transition have been analyzed within the McCumber theory to yield the peak emission cross-section and figure of merit (FOM) for the amplifier gain. It appears that the glass containing MgO as a modifier is characterized by the largest FOM suggesting that the fluorotellurite matrix with this oxide can be a good novel host for Er 3+ ion doping. Finally, we propose a new simple method to calculate the mean transition energy of the McCumber approach as the arithmetic average of the barycenter wavenumbers of absorption and emission spectra. [ABSTRACT FROM AUTHOR]

We have investigated the thermal and spectroscopic properties of Pr 3+ -doped new tellurite matrix with the molar composition 60%TeO 2 –27%WO 3 –10%PbO–3%Lu 2 O 3 (TWPLu). The differential thermal analysis has shown that addition of Lu 2 O 3 to the glass results in an increasing resistance against crystallization. The ellipsometric data have provided a Sellmeier-type dispersion relations of the refractive index of the investigated glasses. The optical absorption edge of the TWPLu matrix has been described within the Urbach approach, while the absorption and fluorescence spectra of the Pr 3+ -doped TWPLu glasses have been analyzed in terms of the standard Judd–Ofelt theory along with the luminescence decay of the 3 P 0 and 1 D 2 levels of the Pr 3+ ion. A significant influence of the Pr 3+ ion concentration on the photoluminescence intensity as well as on decrease of the lifetimes of both levels has been explained by a non-radiative energy transfer between the ions through cross-relaxation and energy migration processes. [ABSTRACT FROM AUTHOR]

We have investigated the thermal and spectroscopic properties of Er3+-doped fluorotellurite glass with the basic molar composition 75%TeO 2 –10%P 2 O 5 –10%ZnO–5%PbF 2 and the glasses modified by substituting 5%TeO 2 by a metal oxide, namely TiO 2 or BaO. As follows from the thermal studies, the glass containing TiO 2 as a modifier exhibits a higher stability against crystallization with respect to two other glasses. The ellipsometric data have provided a Sellmeier-type dispersion relation of the refractive index of the investigated glasses. The absorption and fluorescence spectra, along with the photoluminescence decay of the 4I 13/2 levels of the Er3+ ion, have been analyzed within the Judd–Ofelt and Fuchtbauer-Ladenburg approaches. It appears that the quantum efficiency of the 4I 13/2 → 4I 15/2 transition is quite high (above 70%), being the highest (97%) for the glass containing TiO 2 as a modifier. The absorption and emission cross-section results for the 4I 15/2 ↔ 4I 13/2 transition show that the glass containing TiO 2 is characterized by the largest figure of merit (FOM) for the amplifier gain and indicate this matrix as a promising new host for doping with rare-earth ions. • The DSC data indicate that the glass containing TiO 2 exhibits a much higher stability against crystallization in comparison to B 2 O 3. • Fluorotellurite glass containing TiO 2 and B 2 O 3 are characterized by the largest figure of merit for amplifier gain. • The theory of Judd-Ofelt and Fuchtbauer-Ladenburg approaches are presented. [ABSTRACT FROM AUTHOR]

In the optical energy gap, visible and near-IR emission of halide phosphate glasses with a composition of 40P2O5-30ZnO-20LiCl-10BaF2 in mol% doped with 3.5 × 104 ppm Pr2O3, referred to as PZLBPr, were synthesized. The UV-VIS-NIR and spectroscopic properties of these glasses were also predicted. The current glasses had broadband emission photoluminescence covering a wavelength range of 1250 to 1700 nm when excited at 455 nm. These bands for near-infrared emission luminescence relate to the transitions 1G4 → 3H5, 1D2 → 1G4, and 3H4 → 3F3, 3F4 in the optical telecommunication window. The significant PL emission wideband was caused by the radiative transition from Pr3+: 1D2 to 1G4. At 445 nm excitation, these glasses exhibited emission bands that corresponded to blue/reddish orange spectral ranges in visible ranges. The prepared glass has a high lasing quality factor (Ω4/Ω6 = 0.9), high optical energy (4.72 eV), and quantum efficiency = 87.3% with FWHM = 156 nm of transition emission from the 1D2 → 1G4 level. As a result, broadband near infrared optical amplifiers can be fabricated from the prepared glasses. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this work was to investigate the spectroscopic properties of Pr3+ ions of various concentrations embedded in a new matrix, namely a tellurite–tungstate glass with the molar composition 60%TeO2–27%WO3–10%PbO–3%La2O3 (TWPLa). The optical absorption edge of the TWPLa matrix has been described within the Urbach approach, while the absorption and fluorescence spectra of the Pr3+-doped TWPLa glasses have been analyzed in terms of the standard Judd–Ofelt (J–O) theory along with the luminescence decay of the 3P0 and 1D2 levels of the Pr3+ ion. A significant influence of the Pr3+ ion concentration on the photoluminescence intensity as well as on decrease of the lifetimes of both levels has been explained by a non-radiative energy transfer between the ions through different cross-relaxation channels. The spectroscopic studies have been completed with ellipsometric measurements providing the dispersion relation of the refractive index of the investigated glasses that has been taken into account in the J–O analysis. [Copyright &y& Elsevier]