Theoretical model and experimental characterization of high-power burst-mode Nd:YAG laser amplification

A theoretical model for high-repetition-rate Nd:YAG laser amplification, including gain clamping due to parasitic lasing, was developed. A small-footprint power amplifier was constructed to experimentally validate the model and increase the fundamental output of a moderate-energy burst-mode laser from 19.9 to 105 mJ per pulse at 250 kHz. Empirical parameters and the full operational space of the power amplifier were established in terms of repetition rate and input pulse energy. The fourth-harmonic output of the amplifier was used for acetone volumetric laser-induced fluorescence of a dynamic gaseous injector in a rotating detonation engine at unprecedented rates up to 250 kHz.