Influence of thulium concentration in KYW and KLuW crystals on spectroscopic and laser properties

We present the spectroscopy and laser performance of Tm:KYW and Tm:KLuW crystals with different doping concentrations of 0.7 at.% - 13.2 at.%. Maximum optical-to-optical efficiency of 60% with output power of 790 mW was obtained with Tm:KLuW laser under diode pumping at 802 nm. The optimum thulium concentrations in KYW and KLuW crystals were calculated basing on determined spectroscopic parameters.