Er³⁺ and Yb³⁺ Codoped Phosphate Laser Glass for High Power Flashlamp Pumping

A novel Yb ³⁺ -Er ³⁺ codoped phosphate glass for high power flashlamp pumping and high repetition rate laser at 1.54μm, designated EAT5-2, is developed. The weight-loss rate of is 1.3×10^-5gcm^-2 h^-1 in boiling water, which is comparable to Kigre's QX--Er glass. Some spectroscopic parameters are analysed by Judd--Ofelt theory and McCumber theory. The emission cross
section is calculated to be 0.73×10 ^-20 cm². The thermo-mechanical roperties of EAT5-2 are modified after an ion-exchange chemical strengthening process in a KNO₃/NaNO₃ molten salt bath. The thresholds for optical damage from the flashlamp pumping are tested on glass rods. A repetition rate of 15Hz is achieved for chemically strengthened glass. The laser experimental results at 1.54μm from flashlamp pumping are also reported.