Regenerative amplification of picosecond pulses in Nd:YAG at repetition rates in the 100-kHz range

An all-acousto-optically switched picosecond Nd:YAG regenerative amplifier has been developed for operation at pulse repetition rates in the 20-100-kHz range. The amplifier produces stable 50-ps pulses at 1064 nm in a TEMOO transverse mode with pulse energies of the order of 20-100 AJ. Generation of the second harmonic at 532 nm in KTP crystal results in conversion efficiencies greater than 40%. Using the frequency-doubled TEMoo output of the regenerative amplifier to pump a two-pass dye amplifier, we have amplified the 50-fs output pulses from an antiresonant ring dye laser to the 200-nJ level and have successfully produced a stable whitelight continuum at a 100-kHz repetition rate. This preliminary demonstration of synchronous dye-laser amplification and continuum generation attests to the overall quality of the regenerative amplifier output and the general utility of this approach for high-repetition-rate amplification. Limitations of the current regenerative amplifier design and scaling to higher pulse energies are briefly discussed.