COMPARISON OF CW LASER PERFORMANCE OF ND-KGW, ND-YAG, ND-BEL, AND ND-YVO4 UNDER LASER-DIODE PUMPING

We have compared the cw laser performance of Nd:KGW, Nd:YAG, Nd:BEL, a nd Nd:YVO4 crystals tinder low-power laser diode end-pumping. Output p ower dependencies on the pump power and the pump wavelength of these d iode-pumped solid state lasers were investigated. The high Nd3+ concen tration of the Nd:KGW samples used in our measurements as well as up-c onversion and exited-state absorption processes in Nd:KGW cause the re duced laser output power dependence on the pump wavelength which was e xperimentally observed. At pump levels up to 270 mW a slope efficiency of eta(sl) approximate to 46% was reached for the Nd:KGW laser. Nd:KG W microchip laser operation with a slope efficiency of eta(sl) approxi mate to 50% was demonstrated. Thermal lensing in Nd:KGW at pump powers up to 3 W was measured.