Spectroscopic properties of thulium-doped crystalline materials including a novel host, La2Be2O5: a comparative study

We present a comparative study of the spectroscopic properties of Tm in sev eral crystalline hosts: YAlO3, Y3Al5,O-12, La2Be2O5, and LiYF4. These mater ials were experimentally characterized in the spectral region accessible to laser diodes, especially in the context of advantages of pumping at 685 ra ther than 785 nm. Using the Fuchtbauer-Ladenburg equation, we also calculat e the emission cross-section spectra from the experimentally measured fluor escence spectra, in the vicinity of the F-3(4)-H-3(6) and H-3(4)-W-13(5) tr ansitions. The lifetimes of the F-3(4)- and H-3(4)- multiplets at room temp erature were measured experimentally. We finally report, for the first time to our knowledge, absorption lines for different optical transitions of Tm in La2Be2O5. (C) 2000 Optical Society of America.