Optical properties of Dy3+ ions in sodium gadolinium tungstates crystal

Dy3+-doped NaGd(WO4)(2) crystal with sizes of about Phi 20x40 mm(2) was grown by the Czochralski technique along the (001) orientation. Polarized absorption spectra, fluorescence spectra, and fluorescence decay curve of Dy3+-doped NaGd(WO4)(2) have been recorded at room temperature. Based on the Judd-Ofelt (J-O) theory, the intensity parameters from the measured line strengths were evaluated. The J-O parameters were used to predict radiative transition probabilities, radiative lifetimes and branching ratios for various excited levels of Dy3+-doped NaGd(WO4)(2) crystal. The luminescent quantum efficiency of the F-4(9/2) level was determined to be approximately 63% for this material. The emission cross-section of the F-4(9/2)-> H-6(13/2) transition was estimated by using the Fuchtbauer-Ladengurg method. (c) 2006 Elsevier B.V. All rights reserved.