Continuous wave 1.6 μm laser action in Er doped garnets at room temperature⋆
- Cite this article as:
- Stange, H., Petermann, K., Huber, G. et al. Appl. Phys. B (1989) 49: 269. doi:10.1007/BF00714646
We report on room-temperature cw laser action of Er3+: Yttrium-aluminum-garnet (YAG) and Er3+: Yttrium-gallium-garnet (YGG) crystals at 1.64 μm. The laser operates from the metastable4 I 13/2 manifold into an upper Stark level of the4 I 15/2 ground-state manifold of Er3+. Due to reabsorption losses, the Er3+ concentration of the laser crystals must be low. Laser pumping at a wavelength of 647.1 nm yields lowest thresholds around 30 mW and slope efficiencies up to 12.7% for Er:YAG. Laser operation in Er:YGG is achieved with higher thresholds of about 200 mW and smaller slope efficiencies of 0.9%. The effective emission cross section in YAG is estimated to be σe≈5×10−21 cm2.