Spectroscopic properties of newly flux grown and highly Yb~(3+)-doped cubic RE_2O_3 (RE = Y, Gd, Lu) laser crystals

摘要

We have developed laser grade and highly Yb~(3+)-doped cubic rare-earth sesquioxides (RE_2O_3, RE = Y, Gd, Lu) single crystals by means of a newly designed high-temperature solution growth method which gives them spectroscopic properties different from those obtained by high-temperature solidification methods. Absorption and emission cross sections, visible anti-Stokes emission, fluorescence decays of the new cubic Gd_2O_3:Yb~(3+) single crystals are presented and compared to those of Y_2O_3:Yb~(3+) and Lu_2O_3:Yb~(3+) crystals. The case of cubic Gd_2O_3:Yb~(3+) is particularly interesting since its basic spectroscopic properties have never been detailed and we were capable of achieving Yb-doping level as high as 20%.