Thermal analysis and CW laser operation at 1.998 µm in end pumped Tm:Yap lasers

Abstract

We report on thermal analysis and continuous wave (CW) laser operation at (1.998µm) of an end pumped Tm: YAP cylindrical laser rod. The Tm: YAP laser rod is pumped at a wavelength of 1.064 μm emitting from an Nd: YAG laser source. A 3W incident pump power is used to generate a maximum laser output of 700 mW, representing 18% slope efficiency. The power of a thermally induced lens in a Tm:YAP laser rod is numerically analyzed and validated experimentally. The focal lengths of the thermally induced lens are directly measured using a Shack-Hartmann wavefront sensor. We have detected a blue up-conversion fluorescence emission before laser operation at 1.998 µm. The obtained experimental results were in good agreement with the numerical calculations.