FLUORESCENCE MECHANISMS AND DYNAMICS OF TM3+ SINGLY DOPED AND YB3+, TM3+ DOUBLY DOPED GLASSES

The mechanisms of Tm3+ --> Tm3+ and Yb3+ double-line arrow pointing left and right TM3+ energy transfers and the F-3(4) --> H-3(6), fluorescences have been investigated in both Tm3+ singly doped and Yb3+, Tm3+ doubly doped glasses. The experimental results show that the Tm3+ 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 F-3(4) --> H-3(6) transition of TM3+ doped in YSGG crystal and other glasses. The regime of energy diffusion among Tm3+ ions is clearly established and the cross-relaxation F-3(4), H-3(6) --> H-3(4), H-3(4) is also proved. Strong upconversion fluorescence corresponding to the F-3(4) --> H-3(6) transition was observed in Yb3+, Tm3+ doubly doped fluorozircoaluminate glass under 980 nm excitation, and the upconversion process was proved to be two-photon processes in this system.