Spectroscopic and stimulated emission characteristics of Nd3+ in transparent Y2O3 ceramics

Nd:Y2O3 ceramic materials have been synthesized using the vacuum sintering technique with the raw materials prepared by the nanocrystalline methods. The TEM measurements reveal the excellent optical quality of the ceramic with low pore volume and narrow grain boundary. The radiative spectral properties of Nd:Y2O3 ceramic have been evaluated by fitting the Judd-Ofelt model with the absorption and emission data. Individual Stark levels for L-2s+1(J) manifolds are obtained from the absorption and fluorescence spectra and are analyzed to identify the stimulated emission channels possible in the Nd:Y2O3 ceramic. Laser performance studies reveal two stimulated emission channels at 1074.6- and 1078.6-nm wavelengths with stimulated emission cross sections of 7.63 X 10(-20) and 6.35 X 10(-20) cm(2). With 1.5 at % Nd:Y2O3 ceramic acting as a laser medium, we obtained a slope efficiency of 32% with 160-mW output power and pump threshold of 200 mW at 1078.6 nm.