INDUCED EMISSION CROSS-SECTION OF ND-Y3AL5O12 CERAMICS

Optical absorption and emission spectra have been measured for Nd-doped Y3Al5O12 ceramics obtained by a urea precipitation method. The optical properties of the ceramics are almost the same as those of single crystals grown by the Czochralski method and floating-zone method, except for a higher background absorption of 2.5-3 cm -1. The energy-level structure for Nd3+ in the Y 3Al5O12 ceramics is determined for a 1-at. % Nd concentration. The induced emission cross section for the 1-at. %-Nd-doped ceramic is calculated to be 4.9×10-19 cm 2, which falls in the range reported for the Nd:Y3Al 5O12 single crystals. The Nd concentration dependence of the emission decay time at the 1064-nm laser wavelength was also measured, and typical concentration quenching was observed. The decay time of the 1-at. %-Nd-doped ceramic is 219 μs, which is slightly smaller than the reported values for single crystals.