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We first demonstrate the laser performance of a compact 2.06 μm Ho: YLF laser resonantly pumped by a broadband fiber-coupled diode. In continuous-wave (CW) operation, maximum output power of 1.63 W, corresponding to a slope efficiency of 89.2%, was obtained with a near diffraction-limited beam quality. In actively Q-switched operation, maximum pulse energy of 1.1 mJ was achieved at the repetition frequency of 100 Hz. The minimum pulse duration was 43 ns. The performance in both the CW and Q-switched regimes indicates that the current fiber-coupled diode in-band pumped Ho: YLF laser has great potential in certain conditions that require several watts of output power or several millijoules of short pulse energy.

We demonstrated the active shaping for a solid-state Nd:YVO₄ amplifier with a high average gain of 39.2 dB. The average output power was 8.3 W with respect to the input power of 1 mW. A range of common and useful pulse shapes was generated at the final output. In addition, a very flat square pulse was produced with a root-mean-square less than 3% in amplitude. A numerical method was proposed to realize active shaping without an experimental test for the Nd:YVO₄ amplifier, showing great potential for the design of lasers with both high peak power (>100  kW) and a desired pulse shape.

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.