Spectroscopic properties of Er3+ doped phospho-tellurite glasses

Erbium doped phospho-tellurite glasses of molar compositions 50TeO2 30P2O5 19Na2O 1Er2O3 and 45TeO2 35P2O5 19Na2O 1Er2O3 are made and their optical and physical properties are studied in comparison to erbium doped sodium-tellurite glass. Differential scanning calorimetry shows an increase in the glass transition temperature with the addition of P2O5. From the infrared transmittance spectra we found that the maximum phonon energy of the phospho-tellurite glasses is also high (∼1290cm-1). Optical absorption spectra of the phospho-tellurite glasses shows a blue shift in the absorption edge comparing to the sample without phosphate. From the optical absorption spectra the Judd–Ofelt parameters (Ωt)(Ωt), transition probabilities, branching ratios of various transitions and their radiative lifetimes are calculated. The absorption and emission cross-section spectrum of the I15/24 to I13/24 transition of erbium in tellurite glass with 30% P2O5 shows almost equal bandwidth and peak cross-sections as in sodium-tellurite glass.