Hydrothermal Growth of Single Crystals of Lu₃Al₅O₁₂ (LuAG) and Its Doped Analogues

The growth of Lu₃Al₅O₁₂ (LuAG) as high quality single crystals using the hydrothermal method is described. The growth protocol is similar to that of Y₃Al₅O₁₂ (YAG) using binary oxides (Lu₂O₃ and sapphire) as feedstocks and 2 M K₂CO₃ as mineralizer. The growth conditions are similar to those of YAG with a dissolution zone temperature of 640 °C and a growth zone temperature of 610 °C. To grow large crystals, commercially available YAG single crystals with (100) faces were used as surrogate seed crystals. The close lattice match allows for high quality growth of LuAG single crystals on the YAG seeds. Preparation of Lu₂O₃ doped with a number of lanthanide ions (Nd, Tm, Er, Yb, Ho) in various concentrations is described, and use of these materials as feedstocks leads to formation of doped LuAG. Similarly, a process for the growth of single crystals of Lu₃Al_<i>x</i>Ga_{(5–<i>x</i>)}O₁₂ with Ga doped in the Al site is also provided. Preliminary absorption spectroscopic data are provided for the various lanthanide doped LuAG crystals