High-average-power (> 20-W) Nd : YVO4 lasers mode locked by strain-compensated saturable Bragg reflectors

摘要

Strain-compensated double InGaAs quantum-well saturable Bragg reflectors (SBR's) with high damage thresholds have been developed for use as mode-locking elements in high-average-power neodymium lasers. Nd:YVO4 lasers have been developed with these new SBR's, which produce transform-limited pulses of 21-ps duration at 90 MHz and an average power of 20 W in a diffraction-limited output beam. The peak pulse power at an output power of 20 W was 10.6 kW. A comparison of the operating parameters of strained single and strain-compensated double-well SBR's indicates that the damage threshold increased by a factor of at least 2-3. Long cavity laser variants were investigated to assess the limitations of further power scaling. At a repetition frequency of 36-MHz stable mode-locked pulses with peak pulse powers of 24.4 kW and pulse energies of 0.6 mu J could be generated. (C) 2000 Optical Society of America [S0740-3224(00)02706-5]. [References: 19]