Publikationsrepositorium - Helmholtz-Zentrum Dresden-Rossendorf

Here we present first lasing and tunability results of a diode-pumped Yb:SiO₂ multicomponent glass laser. The multicomponent glass consists of 70 mol% SiO₂, 20 mol% Al₂O₃, 9.1 mol% La₂O₃, and a doping level of 0.875 mol% Yb₂O₃. Due to the high contingent of SiO₂ the spectroscopic properties of the multicomponent glass is similar to Yb-doped fused silica glass. The huge advantage of the here presented multicomponent fused silica glass as gain material is its fabrication technique. It can be produced directly out of a glass melt with large active volume and high optical quality.
The Yb-doped multicomponent glass sample in the experiment had a thickness of 1.5 mm and was polished in laser quality. For pumping a fiber coupled laser diode was used with power of 6W at 975nm. The pump absorption was about 60%. In order to increase the pump absorption the non-absorbed pump was re-imaged back into the Yb:SiO₂. The laser cavity was a V-shaped resonator and the folding mirror had a curvature of 200mm. This results in a stable confocal resonator with a beam waist of about 50 µm in the glass and 600 µm on the output coupler. The free running laser wavelength was centered around 1055nm. The slope efficiency results in a value of 32%. The wavelength tunability of the laser cavity was achieved inserting a brewster prism (SF10) in between the folding mirror and the output coupler. At a pump level of 5W the laser had a tuning range from 1010 nm to 1080nm.