Intracavity thermal loading measurements and evaluation of the intrinsic fluorescence quantum efficiency in Yb~(3+):LiNbO_3:MgO lasers

摘要

Direct intracavity thermal loading measurements have been performed on diode pumped Yb~(3+) doped LiNbO_3: MgO laser crystals. The fractional thermal loading has been found to be strongly dependent on the Yb~(3+) concentration, decreasing more than 40% when the Yb~(3+) concentration increases from 0.5 to 2 at. %. From the analysis of the concentration dependence of the fractional thermal loading, the intrinsic fluorescence quantum efficiency (free of radiation trapping) of Yb~(3+) ions in LiNbO_3: MgO crystals has been determined and the role of radiation trapping among Yb~(3+) ions is discussed.