Luminescence and spectroscopic properties of ZnF2–MO–TeO2 glasses doped with Ho3+ ions

Doped tellurite glasses: Extending near‐infrared emission for near‐2.0‐μm amplifiers

“…The trend of J-O intensity parameters for the Tm 3+ -doped TBZLN glass (Ω 2 >Ω 6 >Ω 4 ) is different compared with fluorophosphate, 16 tellurite, 17 germanate, 18 and BGN 19 glasses (Ω 2 >Ω 4 >Ω 6 ). On the other hand, the present Ho 3+ -doped TBZLN glasses as well as silicate, 20 tellurite (ZTHo), 21 BiGeZn, 22 ZnAli-BiB 23 glasses exhibit the parameters follow the trend as Ω 2 >Ω 4 >Ω 6 . It is well known that Ω 2 parameter is more sensitive to local environment and covalency of the metal- ligand bond through the nephelauxetic effect.…”

“…From Table II, it is observed that for Tm 3+ ion-doped TBZLN glass, Ω 2 parameter (6.79 9 10 À20 cm 2 ) is higher than other Tm 3+ -doped fluorophosphate, 16 tellurite, 17 germanate, 18 and BGN 19 glasses, indicative of strong covalency and asymmetry between Tm-O bond. In the case of Ho 3+ ions in Tm 3+ / Ho 3+ -codoped TBZLN glass, Ω 2 parameter (3.14 9 10 À20 cm 2 ) shows higher covalency and asymmetry between Ho-O bond when compared to Ho 3+ -doped zinc-tellurite 21 and BiGeZn 22 glasses but lower covalency and higher symmetry around the Ho 3+ ion compared to ZnAlBiB glass, 23 respectively.…”

“…This procedure is standard and well used in literature. [6][7][8][9] The experimental (f exp ) (from the absorption spectra) and calculated (f cal ) (using J-O theory) oscillator strengths for TBZLN-Tm4 and TBZLN-TmHo4 are presented in Table I 21 BiGeZn, 22 and ZnAliBiB 23 glasses, exhibit the parameters follow the trend as Ω 2 >Ω 4 >Ω 6 . It is well known that Ω 2 parameter is more sensitive to local environment and covalency of the metal-ligand bond through the nephelauxetic effect.…”

“…From Table 2, it is observed that for Tm 3+ ion-doped TBZLN glass, Ω 2 parameter (6.79910 À20 cm 2 ) is higher than other Tm 3+doped fluorophosphate, 16 tellurite, 17 germanate, 18 and BGN 19 glasses, indicative of strong covalency and asymmetry between Tm-O bond. In the case of Ho 3+ ions in Tm 3+ -/Ho 3+ -codoped TBZLN glass, Ω 2 parameter (3.14910 À20 cm 2 ) shows higher covalency and asymmetry between Ho-O bond when compared to Ho 3+ -doped zinctellurite 21 and BiGeZn 22 glasses but lower covalency and higher symmetry around the Ho 3+ ion compared with ZnAlBiB glass, 23 respectively. In the following, the J-O intensity parameters (Ω k ) are used to estimate a series of spectroscopic parameters such as spontaneous transition probabilities (A rad ), total radiative transition probabilities (A T ), branching ratios (b), and radiative lifetimes (s rad ) for certain excited levels of Tm 3+ ions and Ho 3+ ions in Tm 3+ -/Ho 3+ -doped TBZLN glasses using the expressions given in literature 15 .…”

“…The J-O intensity parameters for 1.0 mol%Tm 3+ in singly doped and 1.0 mol%Ho 3+ in the codoped TBZLN glasses are presented in Table 2 20 tellurite (ZTHo), 21 BiGeZn, 22 ZnAli-BiB 23 glasses exhibit the parameters follow the trend as Ω 2 >Ω 4 >Ω 6 . It is well known that Ω 2 parameter is more sensitive to local environment and covalency of the metal- 16 tellurite, 17 germanate, 18 and BGN 19 glasses, indicative of strong covalency and asymmetry between Tm-O bond.…”