Inband-pumped Er:Lu2O3 laser near 1.6 µm

For high-power lasers the requirements on the thermo-mechanical properties of the host material increase, demanding for a high heat transfer coefficient and good mechanical strength of the host medium. Compared to the well established YAG crystal, the Lu₂O₃ crystal has a better heat transfer coefficient and a good mechanical strength, making this host interesting for high-power laser application. First inband-pumped laser experiments of Er:Lu₂O₃ were performed with 19 mm long and 1.9 mm diameter laser crystal with a doping concentration of 0.3 %. Two fiber-coupled laser diodes, each emitting at about 1533.5 nm, are used as pump sources from both ends. The folding mirrors of the cavity were specified to reflect at 1645 nm, so the Er:Lu₂O₃ laser oscillated at the emission peak of 1647 nm, where the emission cross section is small. The improvement of the laser performance at other wavelengths will be tested in the near future with optimized resonator mirrors.