Fabrication and characterization of sol-gel GeO2-SiO2 erbium-doped planar waveguides

GeO2-SiO2 sol-gel planar waveguides doped with Er were deposited by spinning on silica substrates. P2O5 Or Al2O3 were used as co-dopants to improve erbium dissolution in the GeO2-SiO2 matrix. Multilayer amorphous films were obtained at 600 or 700 degrees C. Er ions in the planar waveguide pumped at 980 nm showed fluorescence features around 1530 nm. Narrow fluorescence spectra (similar to 20 nm) and long lifetimes (similar to 6 ms) were found in P2O5 co-doped samples, whereas Al2O3 co-doping Save wider spectra (similar to 50 nm) with slightly lower lifetimes (similar to 5 ms). The quenching concentration in the Al2O3 co-doped samples was 0.9 mol% Er. Heat treatments in CCl4 improve the active properties and the addition of Yb enhances the pump absorption efficiency.