Abstract: Neodymium-doped yttrium aluminum garnet (Nd:YAG) transparent ceramic with doping concentration of 1.0at％ was fabricated by a solid state reaction method and vacuum sintering. The absorption spectrum and the fluorescence spectrum of the sample were measured. The highest absorption peak is centered at 808nm and the absorption cross section is 3.1×10^-20cm². The main emission peak is at 1064nm, and the fluorescence lifetime is 257μs. The Judd-Ofelt intensity parameter Ωλ(λ=2, 4, 6), spontaneous transition probability, fluorescence branching ratio and radiative lifetime of Nd3+ were calculated by Judd-Ofelt theory. Finally, the stimulated emission cross section of ⁴F_3/2→⁴I_11/2 transition calculated is 3.81×10^-19cm². It is found that the prepared Nd:YAG transparent ceramic has large stimulated emission cross section and high fluorescence quantum efficiency, which is a potentially excellent laser material.

Key words: Nd³⁺ ion, YAG transparent ceramic, spectroscopic properties, judd-ofelt theory