title: Efficient spectral-step expansion of a filamenting laser pulse.
abstract: We report an efficient transfer of 800 nm energy into both the ultraviolet and the far infrared (IR) during the filamentation in air of an appropriately shaped laser pulse. The multiorder enhancement of the IR supercontinuum in the 3-5 μm atmospheric transmission windows was achieved thanks to spectral-step cascaded four-wave mixing occurring within the spectrum of the shaped femtosecond laser pulse. These results also point out the limit of the self-phase modulation model to explain the spectral broadening of a filamenting laser pulse.
authors: Defence R&D Canada Valcartier, Québec (Qc), Canada. francis.theberge@drdc‑rddc.gc.ca
authors: Francis
authors: F
authors: Théberge
authors: Philippe
authors: P
authors: Lassonde
authors: Stéphane
authors: S
authors: Payeur
authors: Marc
authors: M
authors: Châteauneuf
authors: Jacques
authors: J
authors: Dubois
authors: Jean-Claude
authors: JC
authors: Kieffer