Spectroscopic studies of Dy ion doped tellurite glasses for solid state lasers and white LEDs.

Rare earth ion Dy-doped tellurite glasses were synthesised in the system of (75-x)TeO-15SbO-10WO-xDyO (TSWD glasses). XRD and FTIR characterizations were used to find the crystalline and structural properties. The intensities of the electronic transitions and the ligand environment around the Dy ion were determined using the Judd-Ofelt (J-O) theory on the absorption spectra of the glasses. The measured luminescence spectra exhibit intense emissions at 574 and 484nm along with less intense emissions around 662 and 751nm. Various radiative properties of the F excited level of Dy ion were calculated for the glasses. Decay profiles were measured to find the life times and quantum efficiencies. Yellow to blue intensity ratio (Y/B), CIE chromaticity coordinates and correlated color temperature (CCT) values are calculated using the emission spectra to evaluate the emitted light. The obtained results suggest the utility of the glasses for potential yellow laser and white LED's applications.