Thermal Effects Analysis of High-Power Slab Tm:YLF Laser with Dual-End-Pumped Based on COMSOL Multiphysics

The thermal effects model of slab crystal was established based on the practical operating conditions of the solid-state laser. To our knowledge, this is the first time to use the simulation software of COMSOL Multiphysics to investigate the thermal model of slab crystal with the complex boundary conditions in detail. And this is also the first time to use this theoretical method to a slab Tm:YLF laser. The results showed that thermal effects of Tm:YLF crystal were enhanced with the increase of the pump power. And the thermal effects increased sharply with the decrease of the size of the pump light along the Y-axis or the increase of the crystal doping concentration. Thermal deformation which produced by thermal lens effect played a leading role of Tm:YLF crystal. Finally, under the premise of elevated the laser output efficiency and ameliorated thermal effects, the optimized parameters were chosen which were the pump size of ω1×ω2=1mm × 6mm and doping concentration of 2.5at.%.