RELAXATION DYNAMICS OF EXCITED-STATES OF TM3+ IN SRGDGA3O7 CRYSTALS ACTIVATED WITH TM3+ AND TM3++TB3+

Contribution of Tm-Tm interaction and of Tm-Tb energy transfer to the relaxation of the H-3(4) and F-3(4) states of Tm in SrGdGa3O7 single c rystal was evaluated. Tm-Tb energy transfer reduces effectively the li fetime of terminal level in a potential H-3(4)-F-3(4) laser transition but gives rise to parasitic nonradiative relaxation of the initial H- 3(4) level. SrGdGa3O7 crystal single doped with thulium possesses comb ination of properties advantageous for laser oscillations near 1.9 mu m, namely high rate of cross relaxation process leading to population buildup on the initial F-3(4) level and relatively high crystal field splitting of the ground H-3(6) level.