Visible emission and energy transfer in Tb <sup>3+</sup> /Dy <sup>3+</sup> co‐doped phosphate glasses
Yan Sun, Fei Yu, Meisong Liao, Ju‐Ping Ma, Xin Wang, Dongbing He, Weiqing Gao, J. C. Knight, Lili Hu
Abstract
Abstract In this work, we systematically study the spectroscopic properties of Tb 3+ /Dy 3+ co‐doped phosphate glasses in the visible spectral region and explore the sensitization role of Dy 3+ in the enhancement of visible fluorescence of Tb 3+ ions. Judd‐Ofelt parameters Ω 2 and Ω 4 /Ω 6 of the phosphate glass as host for Tb 3+ are calculated as 21.60 × 10 ‐20 cm 2 and 0.73, respectively, based on the measured spectral absorption. Multiple energy transfer (ET) routes from Dy 3+ to Tb 3+ and their efficiencies are characterized, and the enhanced fluorescence properties of Tb 3+ are investigated, including the emission spectral strength and the spontaneous emission lifetime as functions of Dy 3+ doping concentration. The efficient nonradiative ET processes between Dy 3+ and Tb 3+ allow a moderate concentration level of Tb 3+ to achieve favorably stronger spectral absorption at blue and ultraviolet wavelengths. Tb 3+ /Dy 3+ co‐doped phosphate glass shows promising potential for phosphors and lasing operation at visible wavelengths.