Novel Chemically Stable Er³⁺-Yb³⁺ Codopded Phosphate Glass for Ion-Exchanged Active Waveguide Devices

A novel Er³⁺-Yb³⁺ codoped phosphate glass, which combines good chemical durability with good spectroscopic properties, is developed for the ion-exchange process. The relevant properties of this glass are presented for reference in the design and modeling of ion-exchanged active waveguide devices. The weight-loss rate of this glass is 1.45 x 10^-5g.cm^-2.h^-1 in boiling water, which is comparable to that of Kigre's Q-246 silicate glass. The emission cross section of Er³⁺ in this glass is calculated to be 0.72 x 10^-20cm² using the McCumber theory. It is found that a planar waveguide with three modes at 632.8 nm is readily realized in this glass from our primary ion-exchange experiments.