Diode pumped 2-jxm lasers using Tm,Ho codoped YLF, LuLF, LuAG and GdVO4 crystals

摘要

Tm, Ho codoped YLF, LuLF.and LuAG and GdVC>4 crystals are very attractive for diode pumped 2-|im lasers. A comparison study of laser performance was made using a diode-pumped, quasi-end-pump scheme at various pulse repetition frequencies and temperatures. At 5 Hz and at an operating temperature of 300 K, normal mode laser output energies of 15.7 mJ (YLF) with a slope efficiency of 7.3%, 26.8mJ (LuLF) with that of 12.6% and 20.0 mJ (LuAG) with that of 10.8% were achieved using 5%Tm and 0.5%Ho, respectively. A Tm,Ho:GdV04 laser was also investigated. It was found, in the case of GdVC>4, that optimum Tm and Ho dopant concentrations were slightly lower than those for garnet and fluoride crystals. Using a 3% Tm,0.3% Ho:GdVC>4 crystal, an output energy of 31.2 mJ with a slope efficiency of 14.5% was obtained in normal mode operation at room temperature.