Dynamics of filament formation in a Kerr medium (with Erratum)

We have studied the large-scale beam breakup and filamentation of femtosecond pulses in a Kerr medium. We have experimentally monitored the formation of stable light filaments, conical emission, and interactions between filaments. Three major stages lead to the formation of stable light filaments: First the beam breaks up into a pattern of connected lines (constellation), then filaments form on the constellations, and finally the filaments release a fraction of their energy through conical emission. We observed a phase transition to a faster filamentation rate at the onset of conical emission. We attribute this to the interaction of conical emissions with the constellation which creates additional filaments. Numerical simulations show good agreement with the experimental results. Includes Erratum from PHYSICAL REVIEW A 74, 069902(E) (2006): We have found an error in this paper. In our calculation of the intensity threshold for breakdown in CS2 we erroneously used the ionization energy of molecular CS2 (10.08 eV). ..