Research on high-brightness green laser based on transient stimulated Brillouin scattering pulse compression

This work utilizes transient stimulated Brillouin scattering (SBS) pulse compression and frequency doubling techniques to achieve narrow-pulse-width, high-brightness green lasers. The results indicate that, without optical breakdown occurring, pulsed lasers with average durations of 180 ps and 140 ps were respectively obtained in FC-72 and HT-230. These durations are shorter than a quarter of the medium's acoustic oscillation period, with the narrowest compression reaching 0.8 tau f (the quarter-acoustic wave oscillation period). The average energy efficiency is 30%, coupled with an ideal beam quality. After frequency doubling in a Type-II phase-matched KTP crystal, the 532 nm pulsed laser achieves a maximum output energy of 40 mJ, with a pulse duration of approximately 130 ps. The RMS fluctuation of output energy is 1.5%, and the maximum frequency doubling conversion efficiency is 72%.