Dy3+-doped phosphate glass fibers for yellow lasers

e report on the fabrication and characterization of Dy3+-doped phosphate glass fibers for applications in yellow lasers. The fibers (core/cladding diameters: 11/125 mu m) were fabricated in the system P2O5-Al2O3-Ba2O-K2O with their core doped with 0.12 at.% Dy3+. For bulk glass, the absorption cross-section sigma(abs) is 0.11x10(-20) cm(2) at 452.4 nm (absorption bandwidth: 8.4 nm), in the range well addressed by blue GaN laser diodes. The transition probabilities for Dy3+ ions are calculated using the Judd-Ofelt theory. The stimulated-emission cross-section in the yellow sigma(SE) is 0.36x10(-20) cm(2) at 574.1 nm, and the luminescence lifetime for the F-4(9/ 2) manifold is 818 mu s, indicating a luminescence quantum efficiency close to unity. mu-Raman and mu-luminescence mapping was performed over the fiber end-facet indicating a homogeneous core composition and a uniform distribution of Dy3+ ions.