1  kHz, 70  mJ, high-energy hundred-picosecond fiber–solid-state hybrid laser amplification

We have demonstrated a 1 µm fiber-solid-state hybrid high-energy laser in the hundred-picosecond range. Operating at a repetition rate of 1 kHz, the output energy was 71.1 mJ with a pulse duration of 63.8 ps. By simulating and analyzing the pumped laser intensity inside crystals of different cross-section diameters, and by utilizing the spherical aberration self-compensation effect, the positive spherical aberration thermal lens of the crystal could be reasonably utilized to compensate for the spherical aberration of the beam; the beam quality is <i>M</i><i>x</i>2=2.10 and <i>M</i><i>y</i>2=2.43. This high-energy multi-stage laser, which does not require pumping optical coupling or insertion of additional spherical aberration compensating elements, can be used in the fields of non-linear frequency conversion and industrial precision machining.