Fluorescence mechanisms and dynamics of Tm3+ singly doped and Yb3+, Tm3+ doubly doped glasses

Abstract The mechanisms of Tm 3+ → Tm 3+ and Yb 3+ ⇔ Tm 3+ energy transfers and the 3 F 4 → 3 H 6 fluorescences have been investigated in both Tm 3+ singly doped and Yb 3+ , Tm 3+ doubly doped glasses. The experimental results show that the Tm 3+ doped in fluorozircoaluminate glass, when the excitation is performed at 790 or 684 nm, has a higher quantum efficiency, longer lifetime and stronger fluorescence than for the 3 F 4 → 3 H 6 transition of Tm 3+ doped in YSGG crystal and other glasses. The regime of energy diffusion among Tm 3+ ions is clearly established and the cross-relaxation, 3 F 4 , 3 H 6 → 3 H 4 , 3 H 4 is also proved. Strong upconversion fluorescence corresponding to the 3 F 4 → 3 H 6 transition was observed in Yb 3+ , Tm 3+ doubly doped fluorozircoaluminate glass under 980 nm excitation, and the upconversion process was proved to be two-photon processes in this system.