Er3+-Ions Doped Lithium-Bismuth-Boro-Phosphate Glass for 1532?Nm Emission and Efficient Red Emission up Conversion for Telecommunication and Lasing Applications

Er3+-ions doped lithium-bismuth-boro-phosphate glass samples were prepared by conventional melt quenching method and their structural, thermal, fluorescence, and decay times of the glasses were investigated. Prepared glass samples exhibits amorphous nature and shows very good thermal stability in the temperature range of RT to 500?°C. Judd-Ofelt (JO) analysis was carried out to obtain the parameters which will evidence the glass system for fibre and lasing applications. The intensity parameters O?(2,4 and 6) and stimulated-emission cross-sections were estimated for present glass system. The magnitude of O2 confirms the covalency nature and compared with available other host. The near infrared emission spectra were measured by 980?nm excitation in which the emission intensity is found to be at 1532?nm for the 4I11/2–4I15/2 transition. The FWHM (78?nm), s(?p) (10.11?×?10−21?cm2), δG (7.93?×?10−28?cm3) and G (9.1?×?10−24?cm2?s), for 4I11/2–4I15/2 transition of present glasses are compared to some of the glass systems. Furthermore, the time decay rate found to be slight decreased from 1.04?ms to 0.90?ms when the concentration increased from 0.1 to 0.5?mol% of Er3+ ions and also all follow the single exponential behaviour which is attributed to the self-quenching effect due to the cross-relaxation channels. McCumber's theory reveals peak emission cross-section value is also good agreement with s(?p) which is 10.11×10−21cm2. The obtained gain coefficient population inversion 40% with broad band of emission proves to consider the present system for C band amplifiers. The up conversion of luminescence spectra upon 980?nm excitation exhibits red emission at 665?nm due to 4F9/2 - 4I15/2 transitions also two photon absorption was obtained for power dependence up conversion

Luminescence and decay characteristics of Tb3+-doped fluorophosphate glasses

Tb3+-doped fluorophosphate glasses with the composition of P2O5–K2O–SrF2–Al2O3–x Tb4O7 (where x = 0.1, 0.5, 1.0, 2.0 and 4.0 mol%) were prepared by a conventional high temperature melt quenching technique and characterized through absorption, emission, excitation and decay measurements. From the emission studies, a strong green emission at around 546 was observed, which corresponds to the 5D4 → 7F5 transition of Tb3+ ion. Green/blue intensity ratios (IG/IB) were evaluated as a function of Tb3+ concentration and vice versa. Higher IG/IB intensity ratio confirms the higher covalency between Tb–O bond and higher asymmetry around the Tb3+ ions in the present fluorophosphate glasses. The decay curves for the 5D4 level of Tb3+ ion were measured and found that they exhibited single exponential nature irrespective to the dopant concentration. The experimental lifetime was determined using single exponential fitting and found that it increased from 2.65 to 2.95 ms when Tb3+ concentration increased from 0.1 mol% to 4.0 mol%. The derived properties were compared to the other Tb3+-doped glasses in order to see the potentiality of the material for visible laser gain media at 546 nm