Comparison of Laser Performance for Diode-Pumped Tm:YLF of Various Doping Concentrations

Abstract: Single-end-pumped laser performance of 2, 4, and 6at. % Tm-doped YLF rods is reported. For the pumping configuration employed, crystal fracture was observed to occur for a thermal load per unit absorption length of ~13W/cm. The 2at. % Tm-doped crystal was found to have a quantum yield of ~90 % of that of 4at. % Tm. However, due to a lower thermal loading density, the maximum possible incident pump power is predicted to be>60 % higher, hence offering a greater output power per rod for the lower doping concentration. Power scaling considerations are discussed with reference to cross-relaxation, upconversion, and thermal loading of the host crystal. OCIS codes: (140.3580) Lasers, solid-state; (140.3070) Infrared and far-infrared lasers; (140.3480) Lasers, diode-pumpe