Doped tellurite glasses: Extending near-infrared emission for near-2.0-m amplifiers

Tm3+-singly-doped and Tm3+-/Ho3+-codoped TeO2-Bi2O3-ZnO-Li2O-Nb2O5 (TBZLN) tellurite glasses were successfully prepared by the melt-quenching technique. Emission characteristics and energy transfer mechanisms were studied upon 785-nm laser diode excitation. A significant enhancement of emission intensity at 1.81m with increasing concentration of Tm3+ ions has been observed while increase in the emission intensity at 2.0m with increasing concentration of Ho3+ has been observed up to the equal concentration of Tm3+ (0.5mol%) in TBZLN glasses. The stimulated emission cross section of Tm3+: (F4H6)-F-3-H-3 (5.20x10(-21)cm(2)) and Ho3+: (I7I8)-I-5-I-5 (4.00x10(-21)cm(2)) in 1.0mol% Tm3+-doped and 0.5mol% Tm3+/1.0mol% Ho3+-codoped TBZLN glasses are higher compared with the reported and are found to be excellent candidates for solid-state lasers operating at similar to 1.8 and 2.0m, respectively. The extension of near-infrared (NIR) emission of Tm3+ with Ho3+ ions provides the possibility of using these materials for broadband NIR amplifiers.