Investigation of the scattering properties of Yb:Y2O3 and its effect on laser parameters

Sesquioxides offer excellent thermal-mechanical properties. They have a high intrinsic thermal conductivity and good mechanical stability. Furthermore doping with rare earth ions in high concentration is possible because of the similar atomic radii. Especially ytterbium is an interesting active ion due to its very simple energy-level-scheme with only two multiplets. Therefore, no excited state absorption or upconversion processes should occur, making these materials well suited for use in lasers where high doping levels are necessary, especially for thin-disk lasers. This work deals with the spectroscopic and scattering properties of Yb:Y₂O₃. A possible reason for the high scattering losses and stress inside Yb:Y₂O₃ could be a phase transition slightly below the melting point of 2430degC.