Sensitized deep-UV excitation of Tm3+ ions in strontium phosphate glasses with Sb3+ co-doping

The novel Tm³⁺/Sb³⁺ co-doped phosphate glasses are studied in response to an improvement of blue light emitting source. The analysis of J-O intensity parameters suggests that the present strontium phosphate glass is an appropriate matrix for Tm³⁺ doping to obtain an enhanced blue emission. The 5 s²-type Sb³⁺ ion serves as a sensitizer to transfer its strong allowed excitation in the deep UV region to Tm³⁺ effectively. PL and PLE spectra show that by Sb³⁺ co-doping, the blue emission of the Tm³⁺ doped strontium phosphate glass is enhanced greatly, while the excitation band of Tm³⁺ extends largely to the deep UV region. The emission decay curves of Sb³⁺ demonstrate the existence of the energy transfer (ET) process from Sb³⁺ to Tm³⁺ with the maximum efficiency and probability of ET as 20.43% and 9.20%, respectively. The emission color of these glasses can be adjusted from warm to cold blue via modulating excitation wavelengths. The present work suggests that Sb³⁺/Tm³⁺co-doped strontium phosphate glasses are promising for applications in blue emitters and plasma display panels.