title: Odd harmonics-enhanced supercontinuum in bulk solid-state dielectric medium.
abstract: We report on generation of ultrabroadband, more than 4 octave spanning supercontinuum in thin CaF2crystal, as pumped by intense mid-infrared laser pulses with central wavelength of 2.4 μm. The supercontinuum spectrum covers wavelength range from the ultraviolet to the mid-infrared and its short wavelength side is strongly enhanced by cascaded generation of third, fifth and seventh harmonics. Our results capture the transition from Kerr-dominated to plasma-dominated filamentation regime and uncover that in the latter the spectral superbroadening originates from dramatic plasma-induced compression of the driving pulse, which in turn induces broadening of the harmonics spectra due to cross-phase modulation effects. The experimental measurements are backed up by the numerical simulations based on a nonparaxial unidirectional propagation equation for the electric field of the pulse, which accounts for the cubic nonlinearity-induced effects, and which reproduce the experimental data in great detail.
authors.forename: N
authors.initials: N
authors.lastname: Garejev
authors.forename: V
authors.initials: V
authors.lastname: Jukna
authors.forename: G
authors.initials: G
authors.lastname: Tamošauskas
authors.forename: M
authors.initials: M
authors.lastname: Veličkė
authors.forename: R
authors.initials: R
authors.lastname: Šuminas
authors.forename: A
authors.initials: A
authors.lastname: Couairon
authors.forename: A
authors.initials: A
authors.lastname: Dubietis