High peak power hybrid MOPA laser with tunable pulse repetition frequency and pulse duration

In this paper, we demonstrated a hybrid master oscillator power amplifier (MOPA) laser with high peak power and widely tunable pulse repetition frequency (PRF) and pulse duration. The first-stage solid-state amplifier was carefully designed to keep good beam quality and supply high gain simultaneously. The maximum peak power of 760 kW was achieved with average power of 42 W, PRF of 50 kHz, pulse duration of 1.1 ns, and near-diffraction limited beam quality. The MOPA laser covers a broad tunable temporal range with 1-100 ns for pulse duration and 50 kHz-1 MHz for PRF. Moreover, we experimentally and numerically figure out that Nd:YVO₄ crystal behaves as if continuous-wave (CW) amplification takes place when PRF is larger than 30 kHz.