A new material for high-power laser fibers

Abstract

We have developed a new technique to produce a Yb-doped fused silica bulk glass which is very well suited for fiber laser applications. The starting point is a liquid suspension of SiO₂ particles which is doped by a solution of rare earth ions. After dehydration, purification and vitrification we achieve a bubble-free homogeneous Yb-doped fused bulk silica, which is further processed by the plasma outside deposition (POD) technique into preforms for active laser fibers with a large active fiber core. The laser function of our Yb-doped silica was successfully proved in a side-pumped fiber laser setup. We present the results of the laser experiments.