Luminescence emission of Tm-Dy ions codoped tellurite glasses under visible light excitation

Tellurite glass with composition 90TeO2-10Nb2O5-10ZnO in mol% codoped with x(Tm2O3/Dy2O3), where x = 10,000, 20,000 and 30,000 ppm were prepared by quenching melting technique. The optical density and photoluminescence properties of this glass were studied. Spectroscopic parameters such as the absorption cross section, σab(λ), emission cross section, σem(λ), effective band width, (Δλ), internal gain coefficient, gR(λ), and the chromaticity coordinates CIE of the emitted light for this glass were computed. The, (σem), (Δλ), and σg(λ) parameters increase from 5.95 × 10−21 to 8.86 × 10−21 cm2, from 123 to 127 nm and from 4.2 to 6.3 dB/cm, respectively when increasing Tm3+/Dy3+ ions from 10,000 to 30,000 ppm in the host glass matrix. Compared the luminescence intensity and spectroscopic parameters in these glasses are greatly enhanced. From CIE results indicate that the emission color varied from blue to white can be achieved by tuning Tm3+/Dy3+ ratio under excitation at 466 nm. The present glasses are found to be a suitable candidate for solid state laser material.