Development of a picosecond Nd:YLF amplifier for a laser-Compton X-ray generator

摘要

A multipass amplifier for a picosecond Nd: YLF laser was designed and developed for the light source of a laser-Compton X-ray generator. The developed amplifier was constructed of a water-cooled Nd:YLF rod (20mm long, 4mm in diameter) and a pair of quasi-CW laser diodes (peak power 1kW) with optical systems for rod pumping. The amplifier was operated as a laser with a generated output energy of 218mJ and slope efficiency of 31 percent at l0Hz. We then operated the laser as an amplifier with 0.4mJ, at l0ps, 1047nm seed light. The amplified energy was 4mJ in the single-pass configuration and 30mJ in the double-pass configuration. The experiment result was compared with the theoretical result derived from the Frantz-Nodvik equation. The results agreed well in the lower energy region but diverged in the higher energy region.