Axial emission and spectral broadening in self-focusing of femtosecond Bessel beams.
We report on the experimental observations of on-axis spectral broadening arising from self-focusing of the axicon-generated femtosecond Bessel beam in water. The observed spectral broadening is interpreted by a nonlinearly phase-matched four-wave mixing process involving the intense conical pump, the axial signal and a conical idler wave.
Dubietis
A
A
Polesana
P
P
Valiulis
G
G
Stabinis
A
A
Di Trapani
P
P
Piskarskas
A
A