Efficient generation of subpicosecond seed pulses at 193 nm for amplification in ArF gain modules by frequency mixing in nonlinear optical crystals

Phase-matched sequential frequency mixing in three ,beta-barium borate crystals was used for efficient generation of subpicosecond UV pulses tunable at approximately 193 nm. Double-pass amplification of these seed pulses in a conventional ArF excimer gain module resulted in 800-fs, 1.5-mJ optical pulses.