We grew several thulium- (Tm-) doped La2Be2O5 crystals and determined the concentration of the incorporated Tm using proton-induced x-ray emission. Polarized absoprtion and emission spectra of Tm:La2Be2O5 were investigated, allowing the stimulated-emission cross section to be estimated with the reciprocity method and the Fuchtbauer-Ladenburg equation. We report lifetime measurements of each of the transitions from the 3F4 to 3H6 multiplet and relate them to the radiative lifetime. In view of these results we revisit the question of Tm:La2Be2O5 as a prospective laser material for laser emission at 1.8 μm in the presense of losses and determine the pumping threshold and slope efficiency for a typical resonator geometry.
|Number of pages
|Journal of the Optical Society of America B: Optical Physics
|Published - 1998