LD-pumped high-power tunable green Pr3+:YLF lasers

We have proposed a composite upper energy level mechanism to achieve an LD-pumped continuous wave (CW) high power widely tunable green lasers based on Pr3+:YLF crystal. Efficient laser emissions were demonstrated under 444 nm pumping corresponding to the composite laser energy level transitions of 3P1→3H5, 3P0→3H5 and 1I6→3H5. The total tuning range covers from 519.0 to 550.5 nm (∼31.5 nm). In response to challenges posed by limited emission cross-sections in the π-polarization, we demonstrate the efficacy of σ-polarization to complement these gaps. When the pump power of 11.4 W was absorbed, 4.88 W of 522 nm laser output was obtained in the π-polarization direction with the maximum slope efficiency of 59%, and 1.46 W of 538.0 nm laser output was acquired in the σ-polarization.