SYNTHESIS OF ND3-CODOPED YAG CERAMICS FOR HIGH-EFFICIENCY SOLID-STATELASERS(,CR3+)

Nd,Cr-codoped transparent YAG (Y3Al5O12) ceramics with excellent optic al properties were fabricated by a solid-state reaction method using A l2O3, Y2O3, Nd2O3, and Cr2O3 powders of 99.99 wt% purity. The mixed po wder compacts were sintered at 1750 degrees C for 20 h under vacuum an d annealed at 1400 degrees C for 20 h in an oxygen atmosphere. The Nd, Cr-codoped YAG ceramics consisted of grain sizes ranging from 5 to 35 mu m and exhibited a pore-free structure. The optical transmittance of a 0.8 at.% Nd,0.4 at.% Cr:YAG ceramic at 1000 nm was nearly equivalen t to that of a 0.8 at.% Nd:YAG single crystal. In addition, the fluore scence intensity of the 0.8 at.% Nd,0.4 at.% Cr:YAG ceramic excited by a xenon lamp was double that of the 0.8 at.% Nd:YAG single crystal.