Optical spectroscopic properties, 0.946 and 1.074 mu m laser performances of Nd3+-doped Y2O3 transparent ceramics

摘要

0.4% Nd3+-doped Y2O3 transparent ceramics have been investigated from their optical absorption and emission properties to the laser performances at two different wavelengths, 0.946 mu m and 1.074 mu m. Absorption spectra in the range 300-1000 nm was measured to perform Judd-Ofelt analysis: the calculated spectroscopic parameters Omega(2), Omega(4) and Omega(6) are 7.59 x 10(-20), 4.04 x 10(-20) and 1.40 x 10(-20) cm(2) respectively. The measured fluorescence and radiative lifetime of F-4(3/2) manifold are determined to be 283 mu s and 328 mu s respectively. The branching ratios of F-4(3/2) -> I-4(9/2) and F-4(3/2) -> I-4(11/2) transitions are 57% and 38% with corresponding stimulated emission cross sections of 1.02 x 10(-2) and 1.16 x 10(-20) cm(2) respectively. Laser experiments, under 0.808 mu m laser diode pumping source, were carried out using a piano-concave resonating cavity. At 1.074 mu m, the maximum output power is 3.5 W for an absorbed power of 13.0 W. The optical-to-optical and slope efficiencies reached 26.9 and 31.1%, respectively. For laser operation at 0.946 mu m, the maximum output power reached 1.0 W for 13.0 W of absorbed power. The optical-to-optical conversion efficiency and slope efficiency were 7.9 and 12.4%, respectively. (C) 2017 Elsevier B.V. All rights reserved.