Efficient generation of the 7th harmonic of Ti:sapphire (114.6 nm) vacuum ultraviolet pulses with 60 fs duration by non-collinear four-wave mixing in argon

The recent advances in femtosecond vacuum UV (VUV) pulse generation, pioneered by the work of Noack et al., has enabled new experiments in ultrafast time-resolved spectroscopy. Expanding on this work, we report the generation of 60 fs VUV pulses at the 7th harmonic of Ti:sapphire with more than 50 al of pulse energy at a repetition rate of 1 kHz. The 114.6 nm pulses are produced using noncollinear four-wave difference-frequency mixing in argon. The non-collinear geometry increases the phase-matching pressure, and results in a conversion efficiency of similar to 10(-3) from the 200 nm pump beam. The VUV pulses are pre-chirpcompensated for material dispersion with xenon, which has negative dispersion in this wavelength range, thus allowing almost transform-limited pulses to he delivered to the experimental chamber.

Automated summary

Recent advances in femtosecond vacuum ultraviolet (VUV) pulse generation have allowed for new possibilities in ultrafast time-resolved spectroscopy. In this study, 60 fs VUV pulses were generated at the 7th harmonic of Ti:sapphire with a pulse energy of over 50 al and a repetition rate of 1 kHz. The pulses, produced using noncollinear four-wave difference-frequency mixing in argon, were pre-chirp compensated for material dispersion with xenon, resulting in almost transform-limited pulses delivered to the experimental chamber.