Energy Levels of Yb3+ in Garnets

The absorption and fluorescence of Yb3+ in yttrium gallium garnet and yttrium aluminum garnet have been investigated to locate the levels of the ground manifold 2F7/2. From the temperature dependence of absorption in the gallium compound, it is concluded that the levels lie at 0, 112, 308, and 550 cm—1. For the aluminum garnet, the fluorescence spectrum can be interpreted in terms of a ground manifold with levels at 0, 140, 490, and 620 cm—1.