Re$^{3+}$:YAG laser ceramics: synthesis, optical properties and laser characteristics

Highly transparent yttrium aluminium garnet ceramics doped with holmium or ytterbium or neodymium are synthesised. The ceramics were made of a mixture of nanopowders synthesised by laser ablation. The structural and spectral characteristics of ceramics are studied. In the samples with holmium Ho$^{3+}$ and neodymium Nd$^{3+}$ ions, lasing was achieved with a slope efficiency of 40 % and 35.3 %, respectively; the maximum laser power exceeded 4 W. The internal absorption and scattering losses for 1 % Nd:YAG ceramics are estimated to be $1.6\times10^{-2}$ cm$^{-1}$.