High-power visibly emitting Pr³⁺:YLF laser end pumped by single-emitter or fiber-coupled GaN blue laser diodes

We demonstrate the high-power continuous-wave operation of a Pr³:YLF laser end pumped by blue laser diodes. As the pump source, we used four 5 W single-emitter blue laser diodes and a >20 W fiber-coupled module. In single-emitter-diode pumping, we obtained pump-limited output powers of 6.7 and 3.7 W at 640 and 607 nm, respectively. We successfully suppressed thermal aberration and obtained an output power of 3.4 W at a slope efficiency of 25% at 640 nm with good beam quality in the fiber-coupled module pumping.