High-power Pr3+:YLF 3+:YLF continuous wave lasers at 691.7 nm, 701.4 nm, 705.0 nm, and 708.7 nm

Lasers from 1 I 6 to 3 F 4 transitions were first demonstrated in a Pr3+:YLF 3+ :YLF crystal by inserting a birefringent filter. Output powers up to 2.44 W, 2.10 W, 2.01 W, and 2.42 W were obtained at 691.7 nm, 701.4 nm, 705.0 nm, and 708.7 nm, respectively. Their slope efficiencies were 19.8%, 16.5%, 15.8%, and 19.4%, respectively. The M x 2 and M y 2 factors were measured to be 2.29 and 2.03 at 691.7 nm, 2.23 and 1.86 at 701.4 nm, 2.31 and 2.08 at 705.0 nm, and 2.41 and 2.04 at 708.7 nm, with corresponding power fluctuations of less than 5.3%, 5.6%, 5.8%, and 2.9%.