Harmonic generation during the self-guided propagation of femtosecond ultraviolet (UV) laser pulses (248-nm, 450-fs) in argon is investigated. The third (82.7-nm) and fifth (49.6-nm) harmonics are generated in the UV filament. The energy-conversion efficiencies for the harmonics are found to be at least two orders of magnitude higher than those reported in the literature for similar gas pressures. The enhancement is attributed to the quasi-phase matching of the harmonics due to the self-guiding of the driving pulse.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)
- Physics and Astronomy(all)