Spectroscopic analyses of Yb,Er:Gd3Ga5O12 crystal as a novel candidate of LD pumped ~3.0 μm laser

40 at%Yb3+,10 at%Er3+:Gd3Ga5O12 crystal was grown for the first time by the Czochralski method. Its absorption spectrum, near-infrared and mid-infrared wavebands fluorescence spectra, as well as the fluorescence decay curves of Er: 4I13/2 and 4I11/2 levels were measured at room temperature. The spectroscopic properties including the fluorescence lifetimes were revealed and compared with 10 at%Er3+:Gd3Ga5O12 crystal. In this work, we firstly observed the ~3.0 μm emission corresponding to Er3+: 4I11/2 → 4I13/2 transition in the grown crystal, which proves the existence of efficient energy transfer between Yb3+ → Er3+, and the energy transfer mechanism was discussed.